See also Logseq, which is an open-source privacy-centric offline-first plaintext-based reimplementation of the UI/UX of Roam Research. The main author is an Emacs user, so obviously a lot of Org-mode influence too, and Org is a supported format.
Basically, think Org Roam, just with Electron instead of Emacs.
https://www.orgroam.com/
Roam Research, what it’s based on, might also be of interest.