I’ve been using Obsidian for a long time. I enjoy it and all of its extensions. However setting up the app and syncthing on all of my systems gets irritating.
Any way, after a little looking around, I found Trillium notes. It doesn’t quite have all the extensions, but is easier to setup. Give it a look, see what you think
I used it for months, but I didn’t like it that much. IIRC, it doesn’t store it’s data as pure markdown files, which is a no go for me. Also: plugins.
The best foss alternative I found so far is the one that starts with K and has a way too long to remember. (I know, but I can’t remember)