As of the time of his confirmation, and even now, there is no confirmation that Persona 5 will be on the Switch, and at the time, neither was Final Fantasy VII.
Call it what you want, but Cloud and Joker's only appearances on Nintendo at this time were in spin-offs. The same can be said of Dante. And I'm sorry to PDMG, but the argument that "Final Fantasy as a whole existed on Nintendo so it doesn't count" is just completely untrue. Note that in Smash, the franchise is listed only as Final Fantasy VII, not the series as a whole. All content in the game is from VII. Like Dante, Cloud's only Nintendo appearance at time of inclusion wasn't even in his own series!