Suggestions by @fridgerat

Spoiler

as Post-Credit Scene in The Batman: Heart of Ice

Willem Dafoe

as Joker in The Batman: Heart of Ice

Jason Isaacs

as Mr. Freeze in The Batman: Heart of Ice

Isabela Merced

as Batgirl in The Batman: Heart of Ice

Taron Egerton

as Robin in The Batman: Heart of Ice

John Cleese

as Alfred Pennyworth in The Batman: Heart of Ice

Rebecca Ferguson

as Catwoman in The Batman: Heart of Ice

Bryan Cranston

as Commissioner Jim Gordon in The Batman: Heart of Ice

Dylan O'Brien

as Robin/Nightwing in The Batman: Heart of Ice

John Cleese

as Alfred Pennyworth in The Batman

Edgar Wright

as Director in The Flash

Emerald Fennell

as Director in Wonder Woman: Amazonian Warrior

Matt Reeves

as Director in The Batman

Matthew Vaughn

as Director in Superman: Man of Tomorrow

Ana de Armas

as Power Girl in Superman: Brainiac

Matthew Goode

as Brainiac in Superman: Brainiac

Carrie-Anne Moss

as Lara Lor-Van in Superman: Brainiac

Jon Hamm

as Jor-El in Superman: Brainiac

Jodie Foster

as Martha Kent in Superman: Brainiac

Harrison Ford

as Jonathan Kent in Superman: Brainiac