Can I get different art for a character I already unlocked?

Yes. Open the character's detail screen and look for the re-roll option next to its portrait — for one credit, Multiverse Explorer generates a brand-new piece of art for that same character, keeping its name, role, and story exactly as they are.

This is different from re-rolling a locked character, which swaps out the role and story for a new one before you've spent anything to unlock it. Re-rolling art only ever touches the image on a character you already own.

Save the current image first

A re-roll replaces the portrait you have — it doesn't keep the old one around as a second option. If you've already sent that character's face to your watch, or just like the current art, save it before you re-roll.