Suggestions by @matthewfenner

Bassem Youssef

as Ra's Al Ghul in Smallville Universe

Score: +1

Harold Perrineau

as Mister Terrific in Smallville Universe

Score: +1

Nadji Jeter

as Hot Spot in Smallville Universe

Score: +1

Ricky Whittle

as Black Adam in Smallville Universe

Score: +1

Brandon Routh

as Shazam in Smallville Universe

Score: +1

Hayden Panettiere

as Dove in Smallville Universe

Score: +1

Kellan Lutz

as Hawk in Smallville Universe

Score: +1

Chris Evans

as The Flash in Smallville Universe

Score: +1

Jared Padalecki

as The Flash in Smallville Universe

Score: -1

Cameron Monaghan

as The Streak in Smallville Universe

Score: +1

KJ Apa

as Arsenal in Smallville Universe

Score: +1

Dacre Montgomery

as Arsenal in Smallville Universe

Score: -1

Bill Hader

as Kite-Man in Smallville Universe

Score: +1

Andy Samberg

as Plastic Man in Smallville Universe

Score: +1

Bill Hader

as Plastic Man in Smallville Universe

Score: -1

Jill Teed

as Maggie Sawyer in Smallville Universe

Score: +1

Chris Gauthier

as Toyman in Smallville Universe

Score: +1

Callum Blue

as General Zod in Smallville Universe

Score: +1

Jaren Brandt Bartlett

as Blue Beetle in Smallville Universe

Score: +1

Annette O'Toole

as Martha Kent in Smallville Universe

Score: +1