RE: Female MC (Genderbender) ok!

#6
http://morfs.nowhere2go.org/ (a disease like the Xgene in Xmen ravages the populace, becoming commonplace during puberty and causes superpowers, furries and gender swaps)

http://whateleyacademy.net/ similar to Morfs, whateley academy is a superpower school, with the same issues as above.

Sorry if I narrowed down on your gender bender portion. But, I remember morfs for that if nothing else. I know others say Whateley is better, but I never really got into it myself enough to know. That being said, some of the morfs stories (and how i found it) are very sexually explicit, and are posted on storiesonline.net
Both are very well built universes, with multiple stores within from different authors.

(just realized the OP was forever ago... and someone else popped it up the list. oh well, other might find this and see those universes worth a read)