Thanks for the advice.

In my life I did move a few times and never experienced symptoms like this, and it definitely took me by surprise. Before moving there, we considered "just trying it" by renting an airbnb. But we figured that there is not much difference between "just trying it" and actually moving there because we were only two back then. And our company was just us + our desktop computers. So we did move, but we kind of forgot we were in test-mode in the process.

Budget definitely is not the issue to move places, but visa/covid/taxes are. It might also make my french tax non-resident status harder to get if I'm moving all over the place. But as you said, my top priority now is getting better.