Suggestions by @ange1e4e5

Jon Peters

as Producer in Valentine (1985)

Score: +1

John Gielgud

as Saruman in The Lord of the Rings (1980s)

Score: +2

Pat Roach

as The Witch-King of Angmar in The Lord of the Rings (1980s)

Score: +2

Industrial Light & Magic

as Visual Effects in Fantastic Four Duology (1995-1997)

Score: +1

William Petersen

as Red Leader in Star Wars Original Trilogy (1997-2003)

Score: +1

Richard Harris

as Jon Arryn in Robert's Rebellion (1997-1998)

Score: +1

Ian McKellen

as Tarkin in Star Wars Original Trilogy (1997-2003)

Score: +1

Tony Todd

as Darth Vader in Star Wars Original Trilogy (1997-2003)

Score: +6

Sam Shepard

as Uncle Owen Lars in Star Wars Original Trilogy (1997-2003)

Score: -1

Tyler Mane

as Chewbacca in Star wars Episode IV a New Hope (1997)

Score: +1

Tony Todd

as Darth Vader in Star wars Episode IV a New Hope (1997)

Score: +2

Sean Astin

as Howland Reed in Robert's Rebellion (1997-1998)

Score: 0

Ray Winstone

as Robert Baratheon in Game of Thrones (2001-2009)

Score: +4

Candy Candido

as Treebeard in The Lord of the Rings Trilogy (1961-1963)

Score: +3

David Prowse

as 1970s in What Actors Could've Played The Terminator in Various Decades?

Score: +3

Carter Burwell

as Composer in Chinatown (1994)

Score: +1

Jack Nicholson

as Carl Showalter in Fargo (1976)

Score: +1

Henry Fonda

as Cardinal Tremblay in Conclave (1972)

Score: +2

James Coburn

as Harvey in The Substance (1994)

Score: +3

Howard Shore

as Composer in The Substance (1999)

Score: +1