Cloud and Joker had very weak connections to Nintendo prior to debuting in the Smash series but they were still OK to include because one, FF7 was originally meant for the N64 and two, though FF7 wasn't on a Nintendo console, Cloud was still in other games on Nintendo platforms and plenty of Nintendo customers like Final Fantasy so Cloud was eligible. And for Joker, Persona Q2 was released about a week before his Smash announcement and there are Nintendo customers that like Persona so Joker was allowed too.