As suggested, re-posting the conversation in a separate thread.
How would Golarion and the specific races deal with the single-sex species/races acquiring trans members? Namely creatures like lamias, harpies and girtablili or hags. Seeing as a sex change is 'perfect' using alchemical and magical methods, as in, there are no physical discrepancies or difficulties, would a trans man hag be able to impregnate a woman with a changeling, or would something else prevent it? What would a 'roost' of harpies think about a member of theirs changing like that? Would the individuals motivation matter much for them? Say, if one of the harpies sees the very low 'pick' of humanoids in their lands, would other harpies consider it a boon or something abominable to destroy? They may even feel pride for being a group with a proper harpy man.
Or would the items that change the sex of a person simply fizzle when single-sex races try to use it?
Thanks for your thoughts, I do love to consider such things in world building.
EDIT: Apparently girtablilus might not be in the category. My bad, considered that that scorpion women might be as hermaphroditic as some species of insects are, leading to interesting conundrums if one was to desire to change the human half. Again, probably my misunderstanding of the race being all half scorpion half human woman.