Looking for a specific lesbian book I can't remember the title of

Hi !

So I'm looking for a lesbian romance book I read a couple of years back. It's about a matriarchal society living on another planet coming to Earth, looking for a friendly relation. They go back to their planet with a lot of people from Earth and I think the two female protagonists were a tall and toned or muscular woman and an " average " woman, I think it was something like soulmates or idk. The Earth woman did not fall for the " alien " right away but the other one did if I remember correctly.

It was not erotica tho, that I'm sure.

Thank you in advance