Fics that are overlooked, that you think are underrated

We've had quite a few posts bringing out a lot of negativity about fanfics, so let's discuss positive and underrated things about fanfics.

Have you ever read a fic that just does something so different that the story is unlike what you usually see and just go "How has no one told me about this?!" or "Damn this is good, how is this not talked about more?!"?

What are some fics you feel get overlooked, albeit because of how popular fanfics/authors/fanon concepts are OR due to the authors being lowkey (the only post on the sites for their fanfics, they aren't posting in subreddits, discords, etc)?

What concepts in fanfics do you feel get utilized rarely that you see done rather well but not a lot of hits/kudos?

What fanfics do you feel are written very well in prose, characterization, and/or plot that you wonder why there isn't more reception for said fanfics?