Suggestions by @sadsamurai

Nicholas Lyndhurst

as Dibbler in The Truth

Score: +1

Nicholas Lyndhurst

as Dibbler in The Truth

Score: +1

Victor Rebengiuc

as Otto Chriek in The Truth

Score: +1

Asia Argento

as Sacharissa Crisplock in The Truth

Score: +1

Alessio Boni

as William de Worde in The Truth

Score: +1

Lee Ridley

as HEX in The Science of Discworld

Score: +1

Lee Mack

as Rincewind in The Science of Discworld

Score: +1

Daniel Radcliffe

as Ponder Stibbons in The Science of Discworld

Score: +1

Jeremy Irons

as The Lecturer in Recent Runes in The Science of Discworld

Score: +1

Gary Oldman

as The Chair of Indefinite Studies in The Science of Discworld

Score: +1

Karin Konoval

as The Librarian in The Science of Discworld

Score: +1

Hugh Grant

as The Senior Wrangler in The Science of Discworld

Score: +1

Michael Rosen

as The Bursar in The Science of Discworld

Score: +1

Brian Blessed

as Henry in The Science of Discworld

Score: +1

David Jason

as Mustrum Ridcully in The Science of Discworld

Score: +1

Ryan Reynolds

as Stitch in Kingdom Hearts (Disney+ Live-Action Series)

Score: -2

Bruce Dickinson

as Narrator in Tower of Terror

Score: -1

James Hetfield

as Accelgor in Video Game Characters

Score: +1