I'm rooting for Joker, but seeing that preview, I think Giorno will win.
The Persona loading screen, the Persona background music, the battle taking place in a palace ALREADY & not for like, the climax....
Heck, Giorno being THE AGGRESSOR, AKA the villain.
Death Battle in both music, & setpieces & choreography & what not, pays homeages to both sides, but it feels like we only saw Joker's side there.
& this looks like the BEGINNING of the battle.
Meaning it'll turn around in the second half to show Giorno's stuff. Possibly a time reversal, with Joker being put in a time loop of attacking Giorno, who already sits on the throne. He's on it at the beginning, & at the end of every loop, making Joker's defeat in that manner all the more "poetic"/"cinematic", you know?
I don't like the idea of Giorno winning, but I think that's what's going to happen here.