As stated by others, when the benchmark is made available this should become possible.
I didn't realize character appearance was saved locally- which would have been the initial concern- so if you did delete your current character for a slot to make a new one that data should be saved locally and you could import it into the benchmark when it is released.
That is- as long as everything goes as they stated it would a few months back. Anyways
this post courtesy of translations from Reinheart should answer what your seeking. I'll quote below as well~