Byllie,
If there are multiple genders and it sounds like you are speaking from a multi-verse point of view. If there are n-dimensional modes of gender then yes whatever a person is wearing at that time is the proper attire for that gender.
Given that in a n-dimensional multi-verse any possible combination of evens has happened and thus whatever may be highly improbable in this dimension is not unlikely in another.
Which would mean that wearing a trashbag and gluing a ribbon on your left arm is the traditional dress for a central European woman in one of the dimensions.
