OK, so hang on . . . in the absence of Elsa being there at that time, the curse would just have gone to Yvonne. And OK, the curse gradually eating her up could turn her into a villainess, fine, fine. But as far as I can tell, in the timeline before we did the time shenanigans, there was no particular sign of either of them bearing this curse, although the future-Elsa, or, um, the Elsa from SOME future, plausibly maybe did. Well, unless the curse manifested to isekai-ed Yvonne as the game villain system (remember that?).
So now we're going to try to change the timeline so one of them DOES have the curse? Or what's going on here?
I dunno. The feeling of the earlier parts of this story being connected to the more recent parts of this story is getting more and more tenuous for me.