Far as I've seen, 1B also does it on hit. Pretty sure there's also another attack I'm not sure of the input on that's an overhead and then it activates on the landing from the jump during/after/whichever it is. Wouldn't be surprised if more moves do it than have been found though. I'm expecting in at least a fair number of characters' cases, we won't see the full movelists for certain until launch.
I think its 66B (or is it A+B) with the jump overhead thing.
As for characters, I don't get this "tira is certain" stuff at all. It's a sc1/2 back to roots game. I'd put her super high on a DLC list with Sets and Hilde, but base game..why? Like yeah she's popular and unique but that doesn't give her better odds making it before characters who were actually playable in SC1/2.
I could see it but I wouldn't bet on it.
Voldo, Astaroth, Cervantes are 0 doubt to me.
Asta being in means rock becomes super unlikely unless DLC. Of all the similar styles I feel like rock was never even cared about by the devs.
Lizardman is in images so it's safe to assume he made it, and it makes sense ( i think he's less iconic than the above 3 so I could somehow see him just being a enemy only reskin or something, but the SC system also makes perfect sense for him).
raph and yun (or hwang, not both) are again fairly iconic styles. You're going to have someone with a rapier ( i don't think amy is likely at all unless they viola her, which is probably the better move because that style is unique for the game)
Looking at the two slots left I really can't imagine the game only having one new character, and nothing about Tira screams "oh clearly she'll be in the game" vs someone like Mi-na who would actually have story ties with Hwang/Yun and was in the original game.