Suggestions by @thegingerbreadman

Thomas Doherty

as Bruce Wayne in Luthor

Score: +1

Holt McCallany

as General Sam Lane in Luthor

Score: +1

Matthew Macfadyen

as Maxwell Lord in Luthor

Score: +1

Taraji P. Henson

as Amanda Waller in Luthor

Score: +1

Mason Dye

as Pete Ross in Luthor

Score: +1

Pom Klementieff

as Mercy Graves in Luthor

Score: +1

John Lithgow

as Lionel Luthor in Luthor

Score: +1

Cody Fern

as Lex Luthor in Luthor

Score: +1

Cody Fern

as Lex Luthor in Superman

Score: +1

Anthony Ingruber

as Hal Jordan in The Flash

Score: +1

Devon Bostick

as The Trickster in The Flash

Score: +1

Josh Helman

as Heatwave in The Flash

Score: +1

Aaron Paul

as Captain Cold in The Flash

Score: +1

Himesh Patel

as Captain David Singh in The Flash

Score: +1

David Castañeda

as August Heart in The Flash

Score: +1

Sigourney Weaver

as Joan Garrick in The Flash

Score: +1

Gregg Henry

as The Flash I in The Flash

Score: +1

Emory Cohen

as Mirror Master in The Flash

Score: +1

Alison Pill

as Iris West Allen in The Flash

Score: +1

Jamie Bell

as The Flash II in The Flash

Score: +1