Suggestions by @rossjames

Jon Hamm

as Thomas Wayne in Batman

Florian Munteanu

as Black Mask in Batman

Emma Stone

as Batwoman in Batman

Brad Kavanagh

as Nightwing in Batman

Tom Selleck

as Commissioner Gordon in Batman

Ian McKellen

as Alfred Pennyworth in Batman

David Tennant

as Joker in Batman

Selena Gomez

as Catwoman in Batman

Dylan O'Brien

as Batman in Batman

Grant Gustin

as Atom in Justice League

Grant Gustin

as Batman in Justice League

Grant Gustin

as Superman in BATMAN/SUPERMAN

Grant Gustin

as Clark Kent in The Batman/Superman: World's Finest

Grant Gustin

as Superman in Superman: The Last Son of Krypton

Grant Gustin

as Tony Stark in Marvel High School

Caity Lotz

as Sara Lance in Invasion! (Arrowverse)

Melissa Benoist

as Kara Zor-El, Kara Danvers in Invasion! (Arrowverse)

Taron Egerton

as Barry Allen in Invasion! (Arrowverse)

Dylan O'Brien

as Barry Allen in Invasion! (Arrowverse)

Stephen Amell

as Oliver Queen in Invasion! (Arrowverse)