Suggestions by @joshthomas

Hugh Laurie

as Professor Samuel Oak in Pokémon: The Complete Saga

+2-0Score: +2

Benedict Cumberbatch

as Mewtwo in Pokémon: The Complete Saga

+1-0Score: +1

Matt Smith

as James in Pokémon: The Complete Saga

+4-2Score: +2

Craig Ferguson

as Professor Samuel Oak in Pokémon: The Complete Saga

+3-0Score: +3

Peter Capaldi

as Professor Samuel Oak in Pokémon: The Complete Saga

+4-0Score: +4

Kathryn Newton

as Lucy Stevens in Pokémon

+3-0Score: +3

Justice Smith

as Tim Goodman in Pokémon

+1-0Score: +1

Matt Smith

as James in Pokémon

+2-0Score: +2

Karen Gillan

as Jessie in Pokémon

+1-0Score: +1

Benedict Cumberbatch

as Mewtwo in Pokemon II

+4-0Score: +4

Benedict Cumberbatch

as Mewtwo in Pokemon: The First Movie (Live action movie)

+6-0Score: +6

Sadie Sink

as Misty in Pokemon: The First Movie (Live action movie)

+16-1Score: +15

Asher Angel

as Ash Ketchum in Pokemon: The First Movie (Live action movie)

+5-2Score: +3

Javier Bardem

as Apocalypse in Wolverine and his Rouge Gallery

+1-1Score: 0

Ryan Potter

as Young Gohan in Dragon Ball Z .

+4-1Score: +3

Mahershala Ali

as Piccolo in Dragon Ball Z .

+4-4Score: 0

Ludi Lin

as Goku in Dragon Ball Z .

+6-1Score: +5

Ryan Potter

as Gohan in Dragon Ball Z - Dream Casting

+2-3Score: -1

Mahershala Ali

as Piccolo in Dragon Ball Z - Dream Casting

+2-3Score: -1

Ludi Lin

as Goku in Dragon Ball Z - Dream Casting

+13-3Score: +10