Why would you want to do that though? O.OYou don't have to do complete the quests manually to switch culti now. Just do the FB89 culti, get a third fairy card, and then get a Celestial Schism Mold and 200 mirages.
Out of curiosity, would that also reset your skills that were sage/demon/primal or would it automatically change it to its counterparts?
I hear in the new expansion that skills will automatically be switched upon converting fairy. Not sure if true or not though.