Sundial Exchange - for Guardian and related canons

For AUs, I'd really recommend:

Reverse Star Chase (逆追星) by bowlerrootx - A super cute, fun story where ZYL and Bai Yu are housemates.
fledgling by bonibaru - Zhu Yilong is a dragon!

And in non-AUs, from Yuletide I loved:

In Plain Sight by no_detective - A lovely, hot story where they start sleeping together early in shooting, and catch feelings later.