@Fui-nee
No, 'why bother with disguise' is correct. This gag (crossdressing disguise) is incredibly dumb.
MC is an impossibly powerful mage, who can hide his presence from trained assassins,
casually turn invisible, and do other reality-bending things like teleportation. He doesn't really need to disguise himself.
That aside, with all that magic he somehow can't change his appearance at all, and on top of that is physically forced into this disguise?
It's bad story consistency and writing.