CSV (UTF-8) to Postgres database (UTF-8), doesn't show äöå characters
I solved my own problem. Everything was right from server side and problem was few little things. My first mistake was that I made two text files that I used in my code to generate users. These two text files was in ANSI encoded. I made them with notepad in windows and didn't think much of it.

Even though Visual Studio Code show these ANSI encoded text-files correctly and writes them inside of UTF-8 csv-file correctly. Even if I open that csv-file with notepad++ it's show's those characters as UTF-8 encoded. However when I pushed them to database they all broke up. Not sure why they show up correctly in UTF-8 file in notepad++? Is there some weird translation correction?

I solved this to convert those ANSI text files to UTF-8 with notepad++.

However my second mistake was that I didn't open those files as UTF-8! So even when I converted them to UTF-8 my Visual Studio tried to read them as latin-1 (ISO-8859-1). This round they where broken before I pushed them to database. I took me while to notice, because end result was still the same as ANSI coded files.

I corrected this with adding encoding="utf-8" to all my open statements. Example here with open('users.csv', 'r',encoding="utf-8") as f: I wanted to be sure that Visual Studio Code will open them as UTF-8 and not some weird format.

This finally solved my issue!! This was really specific problem, so I'm not sure if this will help anyone else. However I wanted to post solution here just in case. I hate those post that just writes up that this is now solved and never tells how.