I’ll share some info I stumbled upon that others here might find helpful.

Since I don’t need geolocation metadata on my notes, I disabled that in the settings. That only has an effect on new notes though.

On the desktop app there is an encircled ‘i’ in the top right corner of every note. There you can few and edit the metadata. But it is quite inconvenient to have to do that for every note individually and it took me a while to find a solution.

This forum post from a team member (Tessus) offers a solution:

there’s no UI button to do that, but I’ll post a SQL statement that will wipe out that data.

Ok, depending on where your profile is, this is the statement that will remove the GPS info: we assume that you use the default location:

sqlite3 ~/.config/joplin-desktop/database.sqlite "update notes set latitude = 0, longitude = 0, altitude = 0"