Seeking advice on visa and health insurance

Not really complicated because having worked in lots of countries is irrelevant. Your wife is Finnish, which belongs to the EU and Schengen. It should be pretty straight forward to get a family reunion visa - unless you have a problem like a serious criminal record or belong to a criminal or terrorist organization. On such a visa you have the right to work even freelancing.

Since you lived in Germany before then you can contact your previous insurance company for a start.

And one rarely needs to pay for help with such things. For some it is complicated if neither partner speaks German but one assumes you know enough after 5 years spent in the country. The issues and offical-dom you will have to deal with are not significantly different than what you would have had to deal with on your previous stay; although post-Brexit your status is changed. But immigrating as a spouse of an EU citizen is not a problem, millions have the same situation.

Many thanks.

Good to know a reunion visa will be sufficient for freelance work.

Maybe you also know about health insurance? In contact with a health insurance company to sign up, it got complicated. As I have pensions from multiple countries the company wanted some information from each. I had shown my pension income but they wanted some information about health care related to pensions. The word ‘Zuschuss’ was mentioned but it was unclear what I needed to get. Any ideas?

Best regards

Simon