Ugh, diving into the AruAni or EruAni tag on AO3 feels like a whole archaeological dig these days. So many fics from the 'Attack on Titan' manga era, you know? 'Linked In Life' used to be the big one for me—this canon-divergent, slow-burn thing where they were mechanics. There was also 'A Trip Down Memory Lane,' which was heavy on the angst and memory loss tropes, hit really hard. Honestly, half the classics I remember are probably orphaned or deleted now, which is a bummer.
Finding the current popular stuff means filtering by kudos on AO3 from the last couple years, but honestly, a lot of the buzz shifted to other pairings after the finale. Some of the newer ones play with AUs more, like coffee shop or fantasy settings. You have to wade through a lot of fics where they're a background ship to LeviHan or something, which is fine, but not if you're there specifically for them.
My personal hack? Check the bookmarks of authors who wrote the big epics. They often have curated lists of similar vibes. Found a few hidden gems that way, stories that didn't get thousands of kudos but nailed their dynamic perfectly.