For me it’s probably Psycho-Pass. I’m usually not a fan of gore and stuff like that, but somehow I keep coming back to this one. Something about the distopian setting just draws me in. It’s a shame that there were only three seasons

Most of the Studio Ghibli movies.

Natsume Yūjin-chō always makes me feel good, always makes me smile

Funny that you mention HxH! I just rewatched it but with my gf this time. It was one of my first so I had forgotten most of it and I was easier to please when I didn’t know better. Promised her it was really good but in the end it was mid af. She completely hated the last chimera ant arc of course and it lasted way longer than I remembered even though nothing ever happens. It’s such a slow arc. She surprisingly enjoyed it, the good parts at least. She’s a fan of Hisoka but has no plan to rewatch this ever again and nor do I lol.

I rewatched Log Horizon seasons 1 and 2 when the 3rd released and that was still really good. I’ve rewatched the early seasons of MHA like twice because those were the best IMO. I’ve rewatched ReLife once. It’s still one of the best animes I’ve ever seen. Very well made and written.

That’s about it for now but I did think about rewatching Code Geass lately. I remember being annoyed a lot back then though and again, it was also one of my first so I might judge it even harsher now but whatever.

Marmalade Boy

Watamote. Still relatable on a spiritual level.

The Monogatari series. You can watch it in almost any order and you get a completely different experience and notice new stuff you haven’t noticed before

I agree with Fullmetal Alchemist Brotherhood.

If anything the themes resonate more and more as I get older, and it’s efficient with very little filler.

Kill La Kill is also fabulous to rewatch, similarly efficient and quick pace.

I really wish Ghost in the Shell held up better, but now that half that stuff is realistic it starts to feel more like a very human-rights violating cop drama. It was easier to have fun and ignore that when the universe they lived in was less real feeling.

I rewatch Azumanga Daioh and Yuru Camp fairly often, but I have Non Non Biyori in a constant state of rewatching

I like to rewatch Kaguya-sama: Love is War every now and then. It’s funny every time. I also re-read the manga from the start pretty much every time a new volume comes out, and there are a lot of volumes!