Blizzard has said that Diablo 3: Ultimate Evil Edition is in development for Xbox One but the release date cannot be told.
For now Diablo 3: Ultimate Evil Edition is announced only for PlayStation 4 and it includes both Diablo 3 and Reaper of Souls, which is an expansion of the game. The lead producer Alex Mayberry said that: “The point is we are developing for Xbox [One] and PS4 simultaneously. We hit those major platforms and then our goal as a development team is to make them run.”
Reaper of Souls is going to be released tomorrow for PC.