Speaking stylistically near-perfect English, but with the thickest of German accents: that's me! The accent is part of me and it remains, after decades of living & teaching in England. Some subconscious bridge to my origins, perhaps?
In earlier generations, this happened a lot among emigrants from Nazi Germany and Austria. Ernst Gombrich, Hans Keller. Listen:
Keller:
https://youtu.be/7QVxfe2qItQ
Gombrich:
https://youtu.be/ea3j-kTnfeU