I'm going to be honest that, if we get a TGA reveal for Fighter Pass 5, no matter what Sakurai said about "Being fun to play is better than being recognizable" I feel that showing the Fighter Pass 5 at the TGA means that said character have a broadcast appeal or out of the Appeal of Nintendo fans, a character that would perhaps be too "out of place" in a Nintendo Direct.
I know we always got the "Smash never ended with Big reveal"
And I'd agree, but for me, Smash Ultimate last reveal was Joker, as it was announced before the game released- which is by itself something preeeetty big, and fit that "Out of the smash/Nintendo fanbase" character.
We now know that the Mii Costumes aren't related to the FP5, and with the recent speaking of Sabi and Vergeben, we know that:
-It's not Ryu
-Not Crash
-Not Scorpion
-Not Geno
-Not Doomguy
Most of them have been big in the speculation circle for most of it (except Scorpion, however like Doomguy, a TGA reveal for him would be natural)
Now, taking into account this, and "what kind of character would being a massive appeal" outside of Nintendo fans, the following are the one I see:
- Dante, obviously is the one I see the most in that case, DMC V did amazingly, and had a live performance of Devil Trigger last TGA. I can see him bring another massive surprise and appeal to everyone, making him a case of "more people happy than unhappy"
-LLoyd, okay, that one is an odd-one, lots of people would say that "BUT TALES OF SYMPHONIA IS NINTENDO!" or heavily related to Nintendo, however I think it's not true as since Tales of the Abyss Portable on 3DS or Vesperia Definitive edition,, we didn't get any Tales of game or mainline tales of game, as they're now mostly/exclusively on Playstations (Alongside the Xillia,2,Graces, Real final version of Abyss and lots and lots of others games.)
-And that last one is just my personal Bias, but I still believe that if Sora is getting announced, it's not in a classic Nintendo Direct, but in one of those mainstream appeal event, like TGA or E3, and with Kingdom Hearts 3 being out this year, and probably absolutely in the best RPG of the year catégory (even if the fans reception was lukewarm at best, the game is still a great game nonetheless), I wouldn't be surprised if he could get his announcement here.