I've seen some adorable ones pop up on Tumblr lately, especially from artists who tag them as 'gojoxyuji' or 'satoru x yuuji'. That pairing has a gentler, more found-family vibe than the heavier stuff, so you'll find a lot of artists leaning into soft, domestic moments.
I wouldn't expect long-form comics on major sites, though. Pixiv has some multi-page doujinshi, but you need an account and navigating the Japanese tags can be tricky. Honestly, most of what I've stumbled across are shorter, 4-panel style comics or single-page illustrations shared on Twitter/X, though the algorithm there is a total mess for finding things reliably.
The real-time updates seem to happen on Discord servers dedicated to 'Jujutsu Kaisen' fanart. Someone will drop a link to a new comic thread from a Korean or Chinese artist on a site like Lofter or Blog.naver, and that's usually how I catch the latest stuff before it gets widely reblogged.