ShonenGamez just ran a story today showing off a new scan of V-Jump in which it is revealed Dragon Ball FighterZ will be getting a brand new character of sorts in Majin Android 21.
Bandai Namco had already revealed the character Android 21 to the world this past fall when details started leaking about the storyline. These leaks showed off the originally created character for the game as one of the main protagonists in the story, but not really revealing anything about her beyond the small piece of video where she interacted with some of the series' most familiar characters.
As you can see from the scanned sheet above, the Majin version of the character is basically the same design with pink skin to match Buu, white hair, and a tail. There are absolutely zero details beyond this, other than to make the assumption that at some point in time, we may see a story where one of the incarnations of Buu melds with Android 21 or brands her to create this new fearsome fighter. If history holds true, now that we've seen these images, it's only a matter of days or maybe a week until we get an official trailer reveal for the character.