I've had the unfortunate mishap of having the perfectly fine English translation of a German site switch to auto translate Dutch crap due to one part using the

I've had the unfortunate mishap of having the perfectly fine English translation of a German site switch to auto translate Dutch crap due to one part using the language preference and the other the IP source, bit weird since as far as I know they usually only offer English. And I can perfectly fine read German so I usually immediately switch to that since some info is not available in English especially with the different Bundesambt websites. What I would like is a browser and os which allows you to set which languages (multiple) never need translating and the site sticking to that.