[Powder]

We can assume it was Mikey in the first live action film ("Pizza! Piiizzaaa!"), & though that baby turtle dialogue was written for the screenplay & likely inspired by the characters love of pizza in the Fred Wolf cartoon, most of the movie was built from the original comics. For me, that's sufficient enough cause to say it was Michelangelo in Mirage as well, but that is of course just head-canon. I think it'd make sense given the context of his personality in the source universe, though, where it's said he is the most talented & emotionally in touch.