This is not a real game. This is a "what if" scenario that shows what a full DBZ game might look like if the Z2 team had the proper resources.
The vast majority of the characters shown on the select screen will never see the light of day. As of now, only Goku, SSJ Goku, Vegeta, Mr. Satan and the Saibamen are available. Gohan, Majin Vegeta and Freeza are coming... after that, Piccolo was said to be planned but that depends on whether or not Balthazaar is still interested in MUGEN or not.
That said, all the stages and the characters I mentioned from this trailer are available for download in MUGEN and are amazing.
Don't expect any updates on this, because technically this game does not exist.