Suggestions by @joshthomas

Sean Pertwee

as Third Doctor in Doctor Who

Reece Shearsmith

as Second Doctor in Doctor Who

Dylan O'Brien

as Iceman in X-Men (MCU)

Rob Hayter

as Hydra Bob in X-Men (MCU)

T.J. Miller

as Weasel in X-Men (MCU)

Alexander Skarsgård

as Sabretooth in X-Men (MCU)

Blu Hunt

as Danielle Moonstar in X-Men (MCU)

Henry Zaga

as Sunspot in X-Men (MCU)

Lana Condor

as Jubilee in X-Men (MCU)

Blair Redford

as Thunderbird in X-Men (MCU)

Alexander Ludwig

as Angel in X-Men (MCU)

Leslie Uggams

as Blind Al in X-Men (MCU)

Alicia Vikander

as Mystique in X-Men (MCU)

Vanessa Kirby

as Emma Frost in X-Men (MCU)

Julianne Hough

as Dazzler in X-Men (MCU)

Alexandra Daddario

as Rogue in X-Men (MCU)

Jon Hamm

as Mr Sinister in X-Men (MCU)

Josh Brolin

as Cable in X-Men (MCU)

Ryan Reynolds

as Deadpool in X-Men (MCU)

Tom Cruise

as Sebastian Shaw in X-Men (MCU)