I'd really like to read a fic, maybe during season 6, during the relationship between Spike and Buffy, where Spike confides in Anya. I think they have a lot of things in common, and I hate how the Scoobies ignore her and Xander treats her like she's stupid. I want that Buffy relizes that Anya can be very helpful with her thousand years of age, she knows a lot of things but nobody listens to her. And Spike is always treated awful even after tries to save Dawn, he's tortured by Glory and during the summer when Buffy's dead help the Scoobies with patrols ect. Fic like this exist?

Not quite but sort of...... A Switch in Time by Coalitiongirl.

Four years after Sunnydale, Buffy must travel back in time to stop Glory and avert the destruction of the world. But there's a catch- she's been accidentally put in the wrong body. She's got all the information necessary to ensure a happily ever after for her friends and herself.
But who's going to listen to Anya?

Then in a completely unrelated rec, read Embers ( a post S8 fic.... yeah yeah) and praise it with all your might. 'Tis a little gem and hasn't been followed much on this site. Sterling fix up of most of S8 excesses....

(If this is inappropriate, sorry Pari)

Second string scoobies has anya taking spike's side along with Tara, Joyce, dawn and Wesley. It's season 5 though and not sure how much the focus is on Spike/anya friendship