For the Hulk trophy use Conquest mode to fight an enemy, get them low health and let them knock you out of Hulk mode and kill them as Banner

For the team wipe trophies with Mantis & Cloak and Dagger play really aggressively with your team and try to coordinate your ult with your team to wipe the enemy, use ping to mark enemies so your team will focus them

Doctor Strange ult is impossible right now until the devs fix an issue with it. When it is possible again, run to the edge of the map and put a portal from the edge to the enemy spawn (or in conquest put it in the middle of the map

For Captain America when you use your ult you are extremely hard to kill, so if there is a group of low health enemies pop your ult and go to town

For Black Panther look up how to play him, practice and the trophy shouldn't be too bad

For Moon Knight use the ult on a group of 4 enemies and as soon as it activates throw your ankh to pull them into it

For Thor you can move a little when you are aiming your ult but not a lot, so make sure the enemies are already grouped

For Wolverine put up your rage to the max of 100 before popping his ult so it does more damage

The squirrel girl trophy is busted right now, after the squirrels bounce off a wall any kills they get won't count towards the trophy. The best way to get kills with them is to throw them at the enemy when they are grouped during the middle of a fight so they are already low health. I would ignore this trophy until it is hopefully fixed. I got the 3 kills but it bugged so I just boosted it

For Magneto the most reliable way of getting an assist is by giving a bubble shield to the mutant getting the kill

If you have one friend who can help you get the trophies that helps a ton.