Suggestions by @egonspengler

Maurice LaMarche

as Egon Spengler in The Ultimate Showdown of Ultimate Destiny

Score: +1

Harold Ramis

as Egon Spengler in The Ultimate Showdown of Ultimate Destiny

Score: +1

Pierce Brosnan

as Erik Strayton in The Ultimate Showdown of Ultimate Destiny

Score: +1

Harold Ramis

as Peggy in Lady and the Tramp (Genderswap)

Score: +1

Harold Ramis

as Honor Blackman in Actors Genderswapped

Score: +1

MacKenna Grace

as Harold Ramis in Actors Genderswapped

Score: +1

Sigourney Weaver

as Harold Ramis in Actors Genderswapped

Score: +2

Annie Potts

as Harold Ramis in Actors Genderswapped

Score: +2

Harold Ramis

as Max Medici in Dumbo (2005 Remake)

Score: +1

Maurice LaMarche

as Dumbo (evil) in Scooby Doo and Guess Who? (Potential New Episodes)

Score: +1

Egon Spengler (Real Ghostbusters)

as Sandy in Grease (toon style)

Score: +1

Gilderoy Lockhart

as Sandy in Grease (toon style)

Score: +1

Mike (Total Drama)

as Cha cha in Grease (toon style)

Score: 0

Egon Spengler (Real Ghostbusters)

as Nurse Wilkins in Grease (toon style)

Score: +1

William Atherton

as Raj in Total Drama

Score: -1

Dan Aykroyd

as Raj in Total Drama

Score: -1

Humphrey Bogart

as Raj in Total Drama

Score: -1

Rick Moranis

as Bowie in Total Drama

Score: 0

Bill Murray

as Bowie in Total Drama

Score: 0

Harold Ramis

as Bowie in Total Drama

Score: 0