Suggestions by @imbatman

Steel (John Henry Irons)

as Iron Man in Marvel vs DC Match ups

Rocket Red (Dmitri Pushkin)

as Iron Man in Marvel vs DC Match ups

Justice League (Team)

as X-Men in Marvel vs DC Match ups

Doom Patrol

as X-Men in Marvel vs DC Match ups

Tigra (Marvel)

as Vixen in Marvel vs DC Match ups

Catwoman (Selina Kyle)

as Tigra in Marvel vs DC Match ups

Vixen

as Tigra in Marvel vs DC Match ups

Cheetah (DCAU)

as Tigra in Marvel vs DC Match ups

Grid (DC)

as Ultron in Marvel vs DC Match ups

Cyborg (Victor Stone)

as Ultron in Marvel vs DC Match ups

Brainiac (Vril Dox)

as Ultron in Marvel vs DC Match ups

Black Mask (Roman Sionis)

as Red Skull in Marvel vs DC Match ups

Deathlok (Luther Manning)

as Cyborg in Marvel vs DC Match ups

Vixen

as Black Cat in Marvel vs DC Match ups

Ava Ayala (White Tiger)

as Catwoman in Marvel vs DC Match ups

Red Lion

as Black Panther in Marvel vs DC Match ups

Catman

as Black Panther in Marvel vs DC Match ups

Anti-Monitor

as Galactus in Marvel vs DC Match ups

Imperiex (DC)

as Galactus in Marvel vs DC Match ups

Ice (DC)

as Emma Frost in Marvel vs DC Match ups