With six Echo fighters already confirmed to be in Super Smash Bros. Ultimate, it doesn't seem like the train is stoppin' any time soon! So let's go over what other potential Echo Fighters could still make it into the game! In addition, I'll also be giving a percentage of how likely I think they are to be added.
Appearing in multiple Donkey Kong games over the years and even being featured in his own mode in Donkey Kong Country: Tropical Freeze, the funkiest Kong around would make for a very easy Echo fighter transition in Ultimate! He shares the same proportions as DK, and most of DK's moves are pretty general and nonspecific, lending themselves well to working with Funky.
To give him a little more spice to separate him from his '82 counterpart, they could incorporate his spinning surfboard in his up-special. And to give him more of a unique feel, they could make him a faster character overall, but also weaker in-turn.
All things considered though, Funky isn't a very highly requested character. Sure he has his fans, but he doesn't have as big of a following as other Echoes like Daisy, Chrom, and Dark Samus. I feel like this makes him less likely than other characters on this list.
Ninten is the very similar-looking NES counterpart to Ness, and the protagonist of the first game in the MOTHER/Earthbound series, MOTHER (or Earthbound Beginnings in the west). There are a lot of similarities between the two characters, which would make Ninten a fitting Echo for this fan-favorite character!
To make him have a unique feel they could make him slower overall, which matches the pace of his source game when compared to its SNES sequel. To compensate, they could make him pack more of a punch. Aside from this and aesthetic differences like animations and sound effects, I can't really think of other ways they could make him feel more than just a copy-and-paste of Ness.
The main thing holding Ninten back is his obscurity, and irrelevance to modern Nintendo. But, if Sakurai wanted to do something really novel for the fans, he could add Ninten which would make all three protagonists of the MOTHER/Earthbound trilogy playable. And since Sakurai seems to be really appealing to the fans this time around, Ninten is possible.
I'll just come out and say it—I know jack squat about F-Zero aside from what has been featured in Smash and Mario Kart. So I have no idea who Black Shadow is, but from what I've seen from around the internet he seems like a popular choice for an Echo and also a villain character to represent the F-Zero series.
I'm not quite sure how they could make him feel unique, besides making him what Ganondorf basically was in Melee—a slower, more powerful Captain Falcon. Maybe he could use some of Captain Falcon's customs moves from Smash 4? I'm honestly not sure.
Really they only reason I can see Black Shadow make it in is because he's a villain, and there seems to be a strong heroes vs villains theme in Ultimate with the additions of Ridley, King K. Rool, and Dark Samus. Aside from that however, Black Shadow doesn't have much going for him, especially considering F-Zero is a dead series at the moment.
Now this one is a little less obvious, but I think Impa would make for a fun and interesting Echo in Ultimate! Sheik's moves seem like they'd transition well to work for Impa, as she has even been a member of the Sheikah in a few games! The only characters in the Zelda series represented in Smash are three different versions of Link, two different version of Zelda, and Ganondorf. I think it's high time we get a new character in the game, and Impa is a top candidate, as she is one of the few reoccurring characters in the Zelda series!
I don't know enough about the character to determine how they could make her feel more unique, but they could maybe pull from Sheik's custom moves from Smash 4 if they wanted to. But the main reason I could see her making it in is because she could represent another branch of Zelda if she took her look from Skyward Sword or Hyrule Warriors. Breath of the Wild, A Link to the Past, Ocarina of Time, Majora's Mask, and Wind Waker are all represented through different characters' designs, and I think Sakurai did this intentionally to broadly represent the Zelda series.
While a lot of the characters I've mentioned so far would only work as Echoes, I think Impa might be too unique to fit in Sheik's moveset. We know proper representation is very important to Sakurai, so maybe an Echo of Sheik wouldn't do her character justice. And even if she was considered as a whole new character, there are other Zelda characters like Skull Kid or the Champions that might be more befitting of a slot on the roster.
Dixie Kong is one of the most popular choices for a new character, and was even considered back in the development of Brawl! But while some could argue that an Echo wouldn't be enough for her, I think the possibility for a new Donkey Kong character has already been filled by King K. Rool, and it's hard to imagine a second new character making it in after him. But, even though there might have to be a lot of changes, I still think Dixie could make for an awesome Echo of Diddy!
The most important change they would have to make would be to replace the animations of a lot of Diddy's melee attacks (especially the ones with his tail) with her ponytail. Her jumps could also change to closer reflect how she acts in her games, although that may make her too unique to be considered an Echo. They could keep most of Diddy's specials, or also pull from his custom moves from Smash 4.
I think a lot of people are riding Dixie Kong off as an Echo fighter. Would it be better if she was a whole new character? Yes, but I think she would end up feeling very similar to Diddy if she was a new character anyway, so why not just make her simpler to develop by making her an Echo? She's a very popular character like Daisy and Chrom, so I think her chances are pretty good.
Shadow the Hedgehog
It's easy to see why Shadow is the most highly speculated Echo for Ultimate, because he's got so much going for him! Similar to other Echo fighters, he shares proportions to his counterpart and is also a very popular and requested character in the Smash community! But, even beyond fan demand, there is some actual evidence pointing to his inclusion. Shadow has previously appeared in both Brawl and Wii U/3DS as an assist trophy, but he appears to have been replaced by Knuckles in Ultimate. Many people, myself included, take this as an almost guarantee that Shadow has been promoted to playable status! There still a possibility that he still is an assist trophy and just hasn't popped up yet, but I highly doubt they'd keep his inclusion such a secret for this long.
So let's say Shadow is added as an Echo fighter; what would be bring to the table? Well, I think he'd have a bunch of unique animations like Dark Samus, and in particular I think it'd be awesome if he ran like he does in Sonic Adventure 2, where he looks like he's rollerblading. And even though he's just as fast as Sonic, I could see them making Shadow a slower, more powerful and methodical character. And for his Final Smash they could keep it the same as Sonic's, but I think there's so much more interesting stuff to pull from! Chaos Control, Space Colony ARK, the Biolizard... so many possibilities!
This might be a little overzealous of me, but I honestly can't think of any discrediting evidence regarding Shadow making it in as an Echo fighter. Highly requested? Check. Very similar to the source character? Check. Absent as an Assist Trophy? Check. Potential for a unique style? Check. Another villain character? Check. I'd never go with a 100% chance on anyone, but I'll get as close to that line as I can for Shadow. I'd be shocked if he doesn't make it in.
Now not very many people are talking about this one, and I suppose I get why. Pikmin is a pretty small franchise (no pun intended), and all of the protagonists are basically interchangeable; Alph is even featured as one of Olimar's alt costumes in Wii U/3DS, as well as in Ultimate. I would have put Alph as the top candidate for an Olimar echo, but since that obviously can't happen now, I'll go with the second best option—Louie. And it'll have to take a Pikmin fanatic like myself to hopefully convince you that he'd be an awesome Echo!
There is one big change that Louie could have that I can see making him a fun Echo: the Rock Pikmin. To make him unique, they could replace Olimar's Purple Pikmin with the Rock Pikmin found in Pikmin 3. Maybe they could have different properties and giving a whole new feel to Louie! And if they wanted to outdo themselves, they could throw in the Bulbmin from Pikmin 2 to replace Olimar's White Pikmin, and would also come with their own properties! They could also make him a slower character to reflect his dopey demeanor, and make him stronger to compensate.
As much as I want to see Louie so we can get as much Pikmin representation as humanly possible, I know it's a long shot. And even on the off-chance that they add Louie, I bet he'd just be an alt costume like Alph, and could maybe be added alongside the other protagonists of the series, being Brittany, Charlie, and the President. I hope he's an Echo though, there are some fun ideas he could bring to the table!
Isabelle, like Shadow, is a very popular character who was an assist trophy in the past and is M.I.A for Ultimate. Kapp'n seems to have replaced her this time around, which suggest she may have gotten the promotion to playable. She has also popped up in many "leaks," and while most of them are obviously fake, it's suspicious that she has shown up in so many of them, lending credence to her case.
All of Villager's moves would translate just fine to Isabelle, because of their generic nature. And beyond using Villager's custom moves from Smash 4 as her own, I'm drawing a blank as to how they can make her feel unique. The main reason she could make it in, aside from the leaks, is that she's the second most popular Animal Crossing character, which is a very popular series that deserves as many reps as it can get. We know how popular she is because she appeared alongside Villager in Mario Kart 8, and she is also the face of the official Animal Crossing Twitter account.
It's weird to imagine Isabelle fighting, but we would have said the same thing about Villager before he was announced for Smash 4. I wouldn't have thought of her myself, but all of the buzz around her inclusion from credible speculators and leakers makes me believe that she's more likely than not.
Alongside her male counterpart, Ms. Pac-Man is one of the most iconic and classic video game characters to come from the arcade era, and was one of the first female characters in all of gaming. I was honestly surprised to see that she wasn't an alt costume for Pac-Man in Smash 4, and since it seems like it'll stay that way for Ultimate, I think it's time she gets her chance to shine by making it in as an Echo fighter!
Ms. Pac-Man and Pac-Man are obviously very similar characters, so the swap would be pretty seamless. A lot of Pac-Man's moves would work just fine for her, because they either reference stuff they share in their respective arcade games or the moves pull from other Namco titles. To make her her own character however, they could change the way her neutral special looks by replacing the fruit and other items with stuff from her own game, like the pretzel and pear items. The developers could also make her a faster character to reflect how she moves faster in her home game than Pac-Man does in his.
Ms. Pac-Man is a very important character in gaming history, and Pac-Man's framework with a few alterations would be a great fit for her. The only reason I could see Nintendo or maybe Namco not wanting her in is because she started out as an unofficial ROM hack made in the US, and not an officially-made character or game. I think her legacy overshadows this, but I'm not sure if Sakurai feels the same way.
Every fighting games has its clones—it's an easy way to squeeze out a few more characters without too much development time! And one of the first fighting games to do this was Street Fighter, who over the years has introduced many clones over their star-character Ryu. And while any of these would work as a great Echo for Ryu, the most recognizable out of them would have to be Ken.
I don't know much about Street Fighter, but from my research I think I can make a good case as to how Ken could be unique. Ken could be a more powerful character, who prioritizes close-up combat over anything else. He could also be a bit faster with his attacks, but to compensate he could be vulnerable for a long time if he misses. He could also have a very bad aerial game, similar to Little Mac.
Ken is the original clone character in fighting games, and after Richter's inclusion in Ultimate, Ken seems like a shoe-in! They might go with other Ryu clones from Street Fighter like Akuma, but I think Ken is the safest and most obvious choice. However, I could maybe see Sakurai not wanting too many 3rd party Echo fighters, and I do think Shadow would take priority over Ken. But still, if Richter is in I think the floodgates are open!
I would say the most talked about Echo fighters are Shadow, Isabelle, and the Octolings. And with the recent popularity spike the Octolings got through the Octo Expansion DLC pack for Splatoon 2, it makes too much sense to make them an Echo fighter over the first newcomer shown for Smash Ultimate—the Inklings.
Sorry if I sound like a broken record by now, but a lot of the same stuff I've brought up about other possible Echoes applies to the Octolings as well. They have practically identical proportions, and all of the Inklings moves would work just fine for them because the two species are literally interchangeable in Splatoon 2's multiplayer. To make them more than a costume, it would be cool to see them use weapons from Splatoon 2 in place of the Inkling's weapons, which all come from the first game. They could all act the exact same, but maybe for the standard special for example the Octolings could use the Splat Dualies instead of the Inklings' Splattershot. They would also have visual and audio differences, and one more thing I'd like to see from them is to have a wider variety of alt costumes! Instead of just the standard style, it'd be awesome to see some stuff from the single player or maybe even Salmon Run!
After seeing that an Echo fighter for a newcomer is possible with Richter, the Octolings seem very likely! The have potential to be unique, and since Splatoon is a very popular series two characters from it would be just fine! The only thing holding them back is that they're pretty new, and have only become playable very recently. And since development for Ultimate started in late 2015, they're probably a little premature to have been in the project plan, which Sakurai and his team usually adhere pretty closely to. But, because DLC is probably going to happen for this game with new characters, stages, and other stuff, I'm going to give the Octolings two scores, because it's very dependent on DLC for the game.
Likeliness in base game: 20%
Likeliness as DLC: 90%
So that just about covers it! Those are all of the major possible Echo fighters that could show up in Super Smash Bros Ultimate, and here's to hoping that some of them actually make it in! And since this was a pretty long article, here are my percentages one more time for each character:
Octoling (DLC): 90% | Octoling (base game): 20%
Dixie Kong: 65%
Ms. Pac-Man: 50%
Funky Kong: 25%
Black Shadow: 5%