Was Dark a book series or a show? Also since you said it was German is it also available in English. it sounds pretty good.
It is a netflix series, so should be available everywhere. It is in German but Netflix has english subtitles, or dubs if you prefer those, although I think it is better with the original voices.
My first thoughts when I realised how the time travel mechanic worked was that it is pretty clearly influenced by Dark as well, several character, and other locations are very similar as well.