i'm not sure to what extent the trophies in melee were made just for that game or just pulled from nintendo's vaults. Mario Golf 64 mainly used N64 promo 3D style for its renders so it wouldn't surprise me if the human characters had models for that in the vaults and just didn't get used. a lot of melee's trophies look like they use models originally intended for n64 era promo art. but yeah it's very likely that model was made for melee. i guess i'm just hyper-aware of instances where nintendo creates a divide between "real mario characters" and characters they've already sentenced to one-off hell. being a long-time fan of the rpgs does that to ya.

Didn't they make the model from scratch?

if only they included the original human characters in these renders. melee proves they had a model for at least Plum.