I hope I understand, if you rotate the head by 180 degrees it looks like you are looking at the front of the head but you are actually looking at the inside of the head, hopefully the gif above is working?  (if not ill upload and send a link)

 

edited, nope it didnt work see below post :)

Tools:- Win10, Dell XPS8900, ZBrush, Marvelous Designer 11, Hex 2, PSP8. PSP 2019 Ultimate, DAZ Studio, Affinity Photo, Affinity Designer, Filterforge 11, flowscape,  Classic UVMapper, and several headache tablets.