Suggestions by @optimistic_writer

Arnold Schwarzenegger

as The Monitor in Crisis on Infinite Earths Part II (2050)

Peter Jackson

as Director in Crisis on Infinite Earths Part II (2050)

Rupert Grint

as Alexander Luthor Jr. in Crisis on Infinite Earths Part I (2049)

Ben Whishaw

as Psycho-Pirate in Crisis on Infinite Earths Part I (2049)

Hayley Atwell

as Harbinger in Crisis on Infinite Earths Part I (2049)

Tony Todd

as Anti-Monitor in Crisis on Infinite Earths Part I (2049)

Arnold Schwarzenegger

as The Monitor in Crisis on Infinite Earths Part I (2049)

Peter Jackson

as Director in Crisis on Infinite Earths Part I (2049)

Eric Stoltz

as Alexander Luthor in The Supermen (2049)

Alex Pettyfer

as Hawk in World's Finest Part II (2048)

Jamie Chung

as Macro in World's Finest Part II (2048)

Sam Rockwell

as Metamorpho in World's Finest Part II (2048)

Danila Kozlovsky

as Geo-Force in World's Finest Part II (2048)

Olivia Cooke

as Halo in World's Finest Part II (2048)

Meisa Kuroki

as Katana in World's Finest Part II (2048)

Brad Garrett

as Leslie "Rocky" David in World's Finest Part II (2048)

Anya Taylor-Joy

as June Robbins in World's Finest Part II (2048)

Jim Carrey

as Walter Mark "Prof" Haley in World's Finest Part II (2048)

Charlie Cox

as Matthew "Red" Ryan in World's Finest Part II (2048)

Brian Austin Green

as Kyle "Ace" Morgan in World's Finest Part II (2048)