Well we also know the Absolute is a single person, female I believe. I am assuming some sort of Drow matriarch(tend to be powerful wiz/sor/clerics) although that is speculation. Perhaps a Drow matriarch got her hands on some forgotten netherese magic and is making a powerplay?
I’m quite sure that the Absolute is an entity for more powerful than a mundane Drow.
Also why female? Is there any indication for it?
No, I think the Absolute has some ties to Bhaal if it's not Bhaal himself. I don't have a lot of evidence, but it seems likely to go there based on the dead three lore spread out around the game. And it would be great