Suggestions by @bumbleprime

Peter Cullen

as Optimus Prime in Scooby-Doo Meets The Transformers (90’s)

John Cleese

as General H. Dawson in Scooby-Doo Meets The Transformers (90’s)

Anjelica Huston

as Marissa Faireborn in Scooby-Doo Meets The Transformers (90’s)

Michael Douglas

as Professor Davis in Scooby-Doo Meets The Transformers (90’s)

Tim Curry

as Nicolas Newman in Scooby-Doo Meets The Transformers (90’s)

Rick Moranis

as Elijah Goodwin in Scooby-Doo Meets The Transformers (90’s)

Neil Patrick Harris

as Zac Cooper in Scooby-Doo Meets The Transformers (90’s)

Holly Hunter

as Lisa Cooper in Scooby-Doo Meets The Transformers (90’s)

Tom Hanks

as Agent Jason Andrews in Scooby-Doo Meets The Transformers (90’s)

Don Messick

as Scooby-Doo in Scooby-Doo Meets The Transformers (90’s)

B.J. Ward

as Velma Dinkley in Scooby-Doo Meets The Transformers (90’s)

Casey Kasem

as Shaggy Rogers in Scooby-Doo Meets The Transformers (90’s)

Heather North

as Daphne Blake in Scooby-Doo Meets The Transformers (90’s)

Frank Welker

as Fred Jones in Scooby-Doo Meets The Transformers (90’s)

Seth Rogen

as Barney Rubble in The Flintstones (Liveaction movie)

Jessica Chastain

as Wilma Flintstone in The Flintstones (Liveaction movie)

Jeff Garlin

as Fred Flintstone in The Flintstones (Liveaction movie)

Kevin James

as Fred Flintstone in The Flintstones (Liveaction movie)

Jeremy Irons

as Soto in ICE AGE (Live Action Remake)

Jeremy Irons

as Soto in Ice age (2002)