They can't add NFT to any Final Fantasy game, unless they make their own game launcher for all of them.

Steam has already made it clear that NFT are not welcome and will remove games that involve them.. seeing as a copy of all current Final Fantasy games are on Steam they will be risking having to refund everyone whose bought a FF game, besides that FF14 is on Steam with a chunk of players who would no longer have the game an throw a fit needing to rebuy and movie their accounts over