I wouldn’t know, and I definitely wouldn’t tell you to search for, for example, “best lesbian science fiction” and then use the goodreads list of some 200 entries as a shopping list on Anna’s Archive.
I’m currently really enjoying the “Defender of the Realm” series - the author gets muddled over details in characters, places, and fight choreography … and sometimes you get exposition in lieu of character development … but the stories are fun :-)
Check out my comment about good erotica, too:
I know this is not 100% what you are asking for, but I want to share my fave erotica site, it’s called The Good Bits. Tons of feminist erotica and erotica written by women for women.
They also have a great filtering/labeling system and tell you how long of a read something is. Tons of options for who is involved: