Does he get the infinity gauntlet? Thanos made the gauntlet according to his hand size. Omni cant fit in it so Omni might die holding the power stone and he won't we able to use all the stones since he doesn't have a place to keep them
Assuming he has the gauntlet
He gets the space stone all by his own. He doesn't even need the power stone
With power and space stone he wins this round. He can't kill Doctor Strange though because of the spell. He will have to torture him which may or may not work
Wins this round too, he was already way powerful than anyone, and now he has turned into the most powerful being in the universe. He gets the mind stone
With all the other stone he either tricks Strange into a false reality to get the stone or he just uses the other infinity stones to get the time stone
He won
In the last battle, Marvel only has Thor and Captain Marvel that can go up against them, but seeing that Viltrumites are slaughtering everybody, either Iron Man, or maybe someone else will do the snap and win the battle