I would like to give all three a shot, but I am probably most excited for VII remake, only because I never played the original. Unlike film, games that are remade tend to be better than their sources because gaming is very tech based (think Resident Evil). So if this game is as good a classic as everyone has made it out to be, I can't wait to play the best version of it to date.
I want to get XV, but the videos I've seen worry me. Haven't played the demo myself, so I can't say for sure that the game doesn't feel right. It just looks like it lacks personality.
I just learned about WoFF and I'm pretty intrigued. The graphics are cute and all (my favorite FF is IX so I don't mind how it harkens back to old school gaming with the chibi like characters), but the best part is the active battle system. Didn't play much of FFXIII, but I didn't enjoy the button mashing. I liked the more methodical, chess like gameplay of the older stuff. Either do that or go full realtime like XV/KH3, but don't do something in the middle like XIII.