For Smash Switch?
Depends on what kind of game it actually is.
If it's like it was speculated and it's just a slightly changed and expanded version of the previous one, so sort of a Deluxe Plus version, then I doubt it.
If they are gonna recycle most of Smash 4's content and only change the most "relevant" characters, then Wario likely won't be a priority.
But if they made the game from scratch and revamped a lot of other fighters as well (like making Ganondorf more unique) then it's more likely.
But all in all I wouldn't hold my breath. I've been let down enough already by this series.