The language in Google maps is not the same with my system language . It's complete English except of little parts like the address line and " Tipps & Tricks" . My system language is german . The bug was in every rom from 10.0.1 till 10.0.12
Tha same for me, i'm from spain and Google maps are in english with android system in spanish....ROM 9.1.17. Unistall and return to install and works ok.