Kokuto:
No, I don't think there have been many individual stories on AO3 recommended, so thank you! I just posted a tag for LYF stories. Will add it to the first pages.
It sounds like an interesting AU ... though I have a hard time imagining CX, of all people, being cool with marrying off XY. Grandfather Daddy must have dragged him to the treaty table kicking and screaming. lol
It's so good, 2 chapters so far, about 1 chapter per week and I'm vibrating for more.
Read at own risk.
It's so terribly logical too, such an obvious route to have taken, which is why I guess the author didn't take it in the novel.
Once everyone knows who's daughter she is, she's the OBVIOUS bridge, as is Xiang Liu.
CX trapped himself by releasing her parental lineage.