Thanks for the reply and help @annajhaveri
I finally figured it out. The uri in the flow written above normally works fine, but somehow my Sharepoint reverts to German language settings when I create a new list from base template in power automate. However, when I create a base list manually in Sharepoint it stays in English.
What adds to the strangeness is that all the column settings I could find in the list created from Power automate said that the column was called "Title" in English, including the URL which said... Guid&Field=Title.
Maybe I should have taken the hint when I suddenly got a error message in German and not in English..
Anyway problem solved, thank you for the help 🙂