Did anyone else notice something about Mulan's face?

Her hair was pulled tight, pulling up the loose skin around the cheeks.

I don't know - she's a cartoon character. It was probably done so that she would look more masculine to the audience.

Well, it was a conscious choice by the animators. They wanted to make her look more angular when she was disguised as a man. But that`s the beauty of animation, to be able to cheat like that.