Suggestions by @jacobking1

Sam McDaniel

as Maynard Gilbough in True Detective in Classic Hollywood

Score: +1

Ray Harryhausen

as Practical Effects in Alien in Classic Hollywood (1950s)

Score: +3

Woody Strode

as Parker in Alien in Classic Hollywood (1950s)

Score: +3

Ben Chapman

as The Alien in Alien in Classic Hollywood (1950s)

Score: +3

Ian Carmichael

as Ash in Alien in Classic Hollywood (1950s)

Score: +3

John Carradine

as Brett in Alien in Classic Hollywood (1950s)

Score: +5

Julie Adams

as Ripley in Alien in Classic Hollywood (1950s)

Score: +3

James Dean

as 1950s in What Actors Could've Played Ferris Bueller in Various Decades?

Score: +2

Hugh Griffith

as Sallah in Indiana Jones in the Golden Age of Hollywood

Score: +3

Kirk Douglas

as Indiana Jones in Indiana Jones in the Golden Age of Hollywood

Score: -1

Thomas Mitchell

as War Doctor in Doctor Who in the Golden Age of Hollywood

Score: +1

John Carradine

as 2nd Doctor in Doctor Who in the Golden Age of Hollywood

Score: +1

Lee J. Cobb

as 12th Doctor in Doctor Who in the Golden Age of Hollywood

Score: +1

Ian Wolfe

as 1st Doctor in Doctor Who in the Golden Age of Hollywood

Score: +2

John Williams

as Bill Tanner in James Bond in the Golden Age of Hollywood (1950s)

Score: +1

Stanley Donen

as Director in James Bond in the Golden Age of Hollywood (1950s)

Score: +1

Edith Evans

as M in James Bond in the Golden Age of Hollywood (1950s)

Score: +1

Leo G. Carroll

as Q in James Bond in the Golden Age of Hollywood (1950s)

Score: +1

Haya Harareet

as Imilce in The Second Punic War in Classic Hollywood (1960s)

Score: +2

Finlay Currie

as Archimedes in The Second Punic War in Classic Hollywood (1960s)

Score: +1