I use Logseq in my PC and my phone and I unse Syncthing to sync the notes accross my devices.

I really hope so, it should be taught, because for me it was a slow learning process. First I started using Obsidian, and moving all my notes from Evernote, Notion, and others manually. After that I moved to Logseq, which is like Obsidian but open-source. And the last step was using an open-source syncing tool (Syncthing) to have my notes synced locally in all devices. And now I have been 2 years self-hosting my notes in a really easy way.