P.DelSlayer said:Masuda has stated that they won't do any DLC that shouldn't be readily available to players.
But what if they do a new region in Pokemon Z and only add the new Pokemon/Formes to X/Y via a free update? That way the new Pokemon and formes would be recognised bij the National Dex in X/Y, but are still only obtainable in Z. That would create the same situation we'll get when the R/S/E-remakes are released: Not all Pokemon are available in-game, but they are recognised in the National Dex and thus would trading restrictions be eliminated