Suggestions by @jamesthethinker

Shawn Levy

as Director in JSA (World Of DC)

Daniel Cudmore

as Atom Smasher in JSA (World Of DC)

Michael Ealy

as Mr. Terrific in JSA (World Of DC)

Gerard Butler

as Hawkman in JSA (World Of DC)

Michael Weatherly

as Flash in JSA (World Of DC)

Kaitlyn Dever

as Stargirl in JSA (World Of DC)

Viggo Mortensen

as Doctor Fate in JSA (World Of DC)

Marshmello

as Echo Echo in FusionFall

Brad Garrett

as Klunk in The Bionic - 6

Frank Welker

as Fluffi in The Bionic - 6

Travis Knight

as Director in The Bionic - 6

Chiwetel Ejiofor

as Martian Manhunter in Martian Manhunter: Man From Mars

Kelly Hu

as Madame-O in The Bionic - 6

Sharlto Copley

as Glove in The Bionic - 6

Dave Filoni

as Director in The Bionic - 6

Stan Bush

as Composer in The Bionic - 6

Mark Strong

as Dr. Wilmer Sharp in The Bionic - 6

Gary Oldman

as Professor Amadeus Sharp in The Bionic - 6

Amanda Fuller

as Drew Saturday in FusionFall

David Oyelowo

as Doc Saturday in FusionFall