My personal pick for that sadly-never-happening-character's actor would be Maisie Williams, aka That One Little Girl From Game Of Thrones Who Can And Will Fuck A Bitch Right The Hell Up.

Actually, thinking about it, Toph is probably described as That One Little Girl From That Weird Cartoon Who Can And Will Fuck A Bitch Right The Hell Up.

Might be a bit difficult to put on the business cards, though...

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"Yeah, I'm definitely going to hell/But I'll have all the best stories to tell" -- Frank Turner, The Ballad of Me and My Friends