Health Insurance with a preexisting condition: how do you insure yourself?


I’m wondering how Digital Nomads with pre-existing conditions insure themselves.

I’m German and most of the German DNs I know keep their primary residence in Germany and go with private health insurance (~150-250€/month) + travel insurance (<50€/month). Sadly that’s not possible for people with pre-existing conditions; those (at least in Germany) are required to voluntarily insure themselves with the governmental healthcare providers at 15.7% of pretax revenue (min. ~350/month, max. ~850€/month).
Probably most other European states work in similar fashion?

The last few years I have gotten along by tricking a little (staying registered as a student), but I’m soon hitting the age limit where that’s not possible anymore and am now looking at either incorporating and paying myself a fixed salary or getting a residency in another European country with a (for self-employed people) more accessible public health system (my main focus is on Portugal’s NHR regime).

Does anyone else here have/had a similar problem? I wonder how others have solved this issue.