They would say cunt a lot more:
“G’day Hermione, how are ya ya cunt?”
“I’m alright thanks Hazza,” replied Hermione, “Ron, did ya get a gander of what that cunt Snape’s up to?”
“Fuck yes! I think he’s—” began Ron, who then stubbed his toe against a vagrant Hoboed Toe-stubber, “Ow! Mother fucking CUNT!”
Aragog would be like 10 times the size!
Everything would be upside down 🗿
They wouldn’t use owls.
They’d use kangaroos.
Muggles would just be called Cunts