> - no translation feature ("gründonnerstag englisch") gives me links to leo.org (which was a cool site in the 00s) and to other sites, but Google gives me a translation box with the result

How about a custom Bang for dict.cc?

Bang shortcut could be "dcc" with URL: https://www.dict.cc/?s=%s.

Then you can translate using "!dcc gründonnerstag".