Story sequence from trailer

Game starts with UCS (instead of Aether) trying to steal Cosmog

At the bridge, instead of being saved by Tapu Koko, Cosmog teleports you to Lanakila and meet UCS.

UCS is now goody goody with you and sends you back. Meets you again at festival.

Lusamine now opens wormhole after you defeat her, but then something else came out.

At altar, after nebby transforms, necrozma comes out, fights and absorbs nebby

You beat him, but then a wormhole appears, teleporting and trapping nebbycrozma at megalopolis. UCS made that wormhole.

Then ???