I think there are plenty of japanese RPGs that you can romance monsters of all kinds if you want to.
In Mass effect series, almost all the female Shepard romance options are aliens and stuff so I suppose that could be made in BG3. If I remember correctly you even get lots of breeding requests for you when you defeat the thresher maw so Those games were much more flexible with interracial love XD
Shouldn´t be a problem to woo a tabaxi, a tortle or even a warforged if you really put your mind into it. Even as a mod. You just going to need a lot of "Mordin advice" about the logistics of the fact.