Suggestions by @jebens1

Lotus Blossom

as Caitlyn in Teenage Mutant Ninja Turtles

Score: +1

Jessica DiCicco

as Velma Dinkley in Scooby Doo and the Loch Ness Monster

Score: +1

Ashley Johnson

as Daphne Blake in Scooby Doo and the Loch Ness Monster

Score: +1

Jason Biggs

as Fred Jones in Scooby Doo and the Loch Ness Monster

Score: +1

Gerard Butler

as Lachlan Haggart in Scooby Doo and the Loch Ness Monster

Score: +1

Ashley Jensen

as Professor Fiona Pembrooke in Scooby Doo and the Loch Ness Monster

Score: +1

David Tennant

as Sir Ian Locksley in Scooby Doo and the Loch Ness Monster

Score: +1

Greg Cipes

as Del Chillman in Scooby Doo and the Loch Ness Monster

Score: +1

Katie Leung

as Kelly Lung in Scooby Doo and the Loch Ness Monster

Score: +2

Louisa Connolly-Burnham

as Shannon Blake in Scooby Doo and the Loch Ness Monster

Score: +1

Matthew Lillard

as Shaggy Rogers in Scooby Doo and the Loch Ness Monster

Score: +1

Jessica DiCicco

as Velma Dinkley in Scooby Doo and the Loch Ness Monster

Score: +1

Ashley Johnson

as Daphne Blake in Scooby Doo and the Loch Ness Monster

Score: 0

Bryce Dallas Howard

as Daphne Blake in Scooby Doo and the Loch Ness Monster

Score: -3

Jason Biggs

as Fred Jones in Scooby Doo and the Loch Ness Monster

Score: +1

Frank Welker

as Scooby Doo in Scooby Doo and the Loch Ness Monster

Score: +1

Winslow Fegley

as Ernie in Scooby Doo on Zombie Island

Score: +1

Dacre Montgomery

as Snakebite Scruggs in Scooby Doo on Zombie Island

Score: +1

Anne Hathaway

as Simone Lenoir in Scooby Doo on Zombie Island

Score: +1

Anna Faris

as Simone Lenoir in Scooby Doo on Zombie Island

Score: -5