At Gamescom in Cologne, Germany, we had a quite interesting chat with Final Fantasy XIV: A Realm Reborn Director and Producer Naoki Yoshida, about the possibility of an Xbox One version of the game.
Yoshida-san explained that he had a meeting with Microsoft a week ago about cross-platform gameplay. However, there are regulations Microsoft has in place about cross-platform games, that dont really adapt well to a MMORPG.
Unless Microsoft adapts those regulations, its really difficult to materialize an Xbox One version of the game. However, Yoshida-san and Microsoft had talks about this topic quite a lot of times already, and next month around Tokyo Game Show another meeting is planned with Microsofts team coming from the headquarters in Seattle. During this meeting, Yoshida-san would like to go over the details of cross platform gameplay.
https://m.youtube.com/watch?v=aMOl9_Ah4RE Around 4:30