Yea it's all true
The dub is fake but the trailer is real.
As big a fan as I am I hope they stop doing this or just give us a new series. This movie takes place in the gap between Buu's death and the last tournament which is a let down for me because that means there isn't going to be really anything new that we haven't seen, I think they should have done it after Goku leaves with Uub so he could see his first test with a real threat(Since I don't count GT and Toriyama is counting this movie as canon and not a side story like the other moive and GT).
I'm going to watch it and will like it I just wish they would give us something better I guess because GT left a sour taste in everyone's mouth, I hope they see Multiverse and decide to make it.