Suggestions by @lukejamesbennett

Charles Sidney Gilpin

as War Machine in Marvel Cinematic Universe (Golden Age of Hollywood)

Robert Williams

as Hawkeye in Marvel Cinematic Universe (Golden Age of Hollywood)

Spencer Tracy

as Hawkeye in Marvel Cinematic Universe (Golden Age of Hollywood)

James Cagney

as Hawkeye in Marvel Cinematic Universe (Golden Age of Hollywood)

John Garfield

as Hawkeye in Marvel Cinematic Universe (Golden Age of Hollywood)

Joan Blondell

as Black Widow in Marvel Cinematic Universe (Golden Age of Hollywood)

Marlene Dietrich

as Black Widow in Marvel Cinematic Universe (Golden Age of Hollywood)

Barbara Stanwyck

as Black Widow in Marvel Cinematic Universe (Golden Age of Hollywood)

Carole Lombard

as Black Widow in Marvel Cinematic Universe (Golden Age of Hollywood)

Joan Crawford

as Black Widow in Marvel Cinematic Universe (Golden Age of Hollywood)

Jean Harlow

as Black Widow in Marvel Cinematic Universe (Golden Age of Hollywood)

Paul Muni

as Hulk in Marvel Cinematic Universe (Golden Age of Hollywood)

Melvyn Douglas

as Hulk in Marvel Cinematic Universe (Golden Age of Hollywood)

Humphrey Bogart

as Hulk in Marvel Cinematic Universe (Golden Age of Hollywood)

Leslie Howard

as Hulk in Marvel Cinematic Universe (Golden Age of Hollywood)

John Garfield

as Hulk in Marvel Cinematic Universe (Golden Age of Hollywood)

Fredric March

as Hulk in Marvel Cinematic Universe (Golden Age of Hollywood)

Spencer Tracy

as Hulk in Marvel Cinematic Universe (Golden Age of Hollywood)

Victor McLaglen

as Thor in Marvel Cinematic Universe (Golden Age of Hollywood)

Clark Gable

as Thor in Marvel Cinematic Universe (Golden Age of Hollywood)