I don’t know of many (other than Wikipedia which is a great option), and I’m not at the level to read real native websites. So I’m not a good person to answer. I’ll watch the thread and maybe come back to these some day. But still, gonna throw some stuff out.

You’re way beyond these, but for fellow beginners that come across this thread, I’ll mention the well-known easy Japanese reading sources: NHK Easy News (if you’re more advanced, there’s also regular news), and the free graded readers at tadoku.org.

Another interesting site I’ve seen is this one that discusses Japanese grammar. Still not quite in the spirit of the question though. There’s this Matcha travel/culture blog, but it also has an English version. And uh… here’s this Pokemon wiki that I’d come across at some point, and this one for Soul Calibur VI. There’s https://tver.jp/ that was posted here a while back, but you probably need a VPN to watch things on it.

Not really a reading site but I like kakijun.jp for stroke order and calligraphy examples.