Which will
never happen as each FF game is an entirely separate world from each other (apart from FFXII being set in Ivalice which first appeared as the world of
FF Tactics, and a tongue-in-cheek and not-to-be-taken-seriously reference by Yoshinori Kitase that FFVII's Planet and X's Spira are in the same universe) - SE even stated
this long ago that Hydaelyn has no connection to any other FF world:
That makes it pretty clear you won't suddenly see FFXI's zones plonked wholesale as an expansion in FFXIV, as the above statement by SE all but shouts why that sort of thing simply will not be happening. FFXI and XIV are totally separate games - they will not be joining the games together or anything. This whole concept is absurd.