This is what I came here to recommend. Logseq is amaze balls and it's completely free and libre unless you want to donate to the project to use their built in sync.
I pay for it since I use it on 5 devices, 2 of which I can't install things on. Logseq doesn't need Admin rights to install since it's always a portable app, but syncing is complicated without Admin rights on a device.
Plus, it's a small team with an ethical business model building this product in beta; I'd probably donate anyway to help ensure it keeps getting development.