Currently only available on PS4 and PC, it seems like Rocket League will soon be coming to Xbox One. As you can see in the image below, the game was listed for Xbox One on the Taiwanese games rating database.
It wouldn't be surprising if Rocket League is indeed going to be released on Xbox One, as Psyonix's VP of marketing and communications Jeremy Dunham has revealed back in August that Rocket League was coming to other platforms. Although he didn't reveal any details about which platforms the game was going to be released, the Xbox One is definately one of the most likely choices for the port. Assuming that Rocket League will be released on Xbox One, the game will surely support cross-play with the PC version, but the same can't probably be said for the PS4 version.
For now, we will have to wait for an official announcement from Psyonix. As a reminder for PS4 and PC players, Rocket League's Chaos Run DLC is out now. This DLC features new battle cars, decals, whells, rocket trails, Trophies/Achievements, and more.