My predictions, based on a couple criteria:
A) They have to be about as notable as Inklings, Ridley, Simon, and King K. Rool
B) They have to be long-standing requests, like Ridley, K. Rool, and Simon
C) They have to be reasonable; no anime or absurd 3rd party characters
D) Can't have strong evidence against them
E) Can't have been realized after the project plan was finished (December 2015)
In other words, they need to be characters that really "wow" people. Everyone's going nuts for Simon and K. Rool, and even Chrom and Dark Samus. If it's just a character that only a small, isolated demographic would be hype about, it's probably not happening. A lot of people don't seem to realize this adn are acting like this is a regular Smash game, when it's instead something special (the Japanese subtitle is "Special" as well), as all these huge and requested characters are getting in. Not ones like Wii Fit Trainer, Duck Hunt, and Pit.
Of course, this means that character reveals won't be too surprising. The most surprising ones were Ridley and Dark Samus, with the former being said to be impossible in the past, and the latter just not being very popular or relevant right now. But we were all waiting for Simon, K. Rool, and Chrom. People expected those. This isn't about defying expectations, it's about satisfying demand.
Newcomers:
- Geno - Haven't played Super Mario RPG yet, don't understand the hype, but I've been hearing people want this guy since Melee. Sakurai's already discussed possibly adding him twice, and he was a Mii Costume in 4, so Sakurai has to know of the demand. Ashley was, too, but I'm assuming that Ashley just doesn't have a whole lot of moveset potential, hence her snub today.
- Skull Kid - Assist Trophy still MIA, and now we have a Moon one. Meant to replace the Skull Kid AT? Maybe. Skull Kid is the most notable villain in Zelda after Ganondorf, and he's also been requested quite a lot. Much like Metroid, Zelda hasn't really had a new rep since arguably Melee, but definitely not since Brawl. Meanwhile Fire Emblem got three in one game and got another today. Part of the problem is that there's been so many additional Zelda characters that have appeared over the years, so it's hard to pick just one. Skull Kid, though, seems to have stood the test of time (hah), so he's the most likely Zelda character we can expect.
- Sora - In the same boat as Cloud, in terms of "Square Enix RPG character that has a rabid fanbase that will die for him." Probably not as requested as Cloud, but has to be pretty close. Many Kingdom Hearts games were exclusive to Nintendo platforms as well, meaning there's some concrete ties to Nintendo that even Cloud didn't have. If we don't get Geno, I expect this.
- Banjo & Kazooie - Microsoft seems completely on board, it's a character more associated with the N64 than anything else, and they've also been requested for a long time. If Sakurai wanted to put them in the game, there wouldn't be anything more in the way than any other third party.
Echo Fighters:
- Shadow the Hedgehog - Sonic characters are always popular, and Shadow more than most. Unfortunately, he probably won't wield an MP5 to gun down aliens in this game. Maybe he can borrow Wario's motorcycle Side-B /s
- Isabelle - One of Vergeben's leaks, and he's been right about everything so far. Plus, there's a lot of support for Isabelle, as she apparently really took off in popularity after New Leaf. Her Assist Trophy is also still missing, just like Dark Samus and Skull Kid. Hm...
- Dixie Kong - Her possibility as an Echo Fighter seemed super unlikely, given that Diddy Kong's Up-B would not fit her character. However, now that we know that Echo Fighters can borrow moves from other characters, as with Chrom having Ike's Up-B, Dixie could maybe borrow someone else's Up-B functionality and have her ponytail animation. Duck Hunt would be a good candidate, I think. But that would cross another line, so who knows. In addition, this would mean that DK and Metroid, two of Nintendo's longest-running franchises that have gotten neglected in Smash for so long, will get both their major requested characters and some Echo Fighters of also requested characters. It'd be pretty poetic.
- Ken/Akuma - Akuma made a guest appearance in Tekken 7, so anything's possible. Ken is equally possible, though maybe not as noteworthy for inclusion. I wasn't too sure about 3rd party Echo Fighters (besides Shadow because he's Shadow), but we got freaking Richter, so I think this is definitely possible.
Things I'm predicting won't happen, not because I don't want them in the game or think they don't belong, but because they're just super unlikely to make the cut compared to everything else we've seen:
- Octolings - I said above that I didn't think they'd happen, and I was right. They're just not distinct enough to warrant an extra slot, even as an Echo Fighter. Plus, Ultimate's project plan was finished in December 2015, and Octolings are only notable now because of the expansion that came out less than two months ago. Kind of surprised so many people thought they were definitely going to happen.
- Rayman - While Nintendo has a very healthy relationship with Ubisoft right now, I don't see Rayman being notable enough to stand beside the likes of Cloud and Simon.
- Bandana Waddle Dee - Same as Rayman, just not notable enough to "wow" people. A lot of Kirby fans are almost completely sure that he's in the game, but that's pretty unreasonable. I'd love to see him, I just don't think it's happening anytime soon.
- Impa - People are saying Sheik Echo Fighter, but that seems redundant. The character's most notable appearance is in Hyrule Warriors, where she wields a giant sword. Is her appearance in Ocarina of Time enough to make it in? I don't think so.
- Another Fire Emblem Character - We got Chrom, that puts us at seven characters. That's one more than Legend of Zelda, and one less than Mario. I think Sakurai knows by now that adding any more would be absurd. But Chrom was important, and people still wanted him, so here we are.
- ARMS character/Spring Man - ARMS is a cool new franchise from Nintendo, but not groundbreaking like Splatoon was. It sold well, but Splatoon is another caliber. Again, the project plan was finished in 2015, a year and a half before ARMS released, so it's unlikely Sakurai would've banked on it that far ahead.
- Solaire - Again, the project plan. Dark Souls 3 wasn't even out when it was completed, so there was probably no plan for the Remastered version, let alone that it'd come to Switch. Heck, it still isn't on Switch because it got delayed indefinitely.
- Rex & Pyra - Project plan, project plan. Game came out late 2017, almost two years after the game started development. It's insane to think that they'd include a character from a game that far out.
- Breath of the Wild Champions - Not only are they after 2015, but there's four of them--how do you choose which one? And they aren't very notable within the game, either. Story and characters weren't BotW's strongsuits. Plus, each of them only has one noteworthy ability and weapon, which is pretty limiting.
- Literally any character after 2015
- Chibi-Robo - *sigh* I got Dark Samus. I'm counting my blessings. I didn't think either of them would ever happen to begin with. But I got one. That's more than most people can say.
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