I was experiencing the same behaviour, and could not pinpoint it to any reason because my system is setup with everything in English – except the keyboard layout, but that never crossed my mind as it didn't make sense, until I read your question.
Looking into the Simulator menu, I realized that the simulator is binding (by default) the keyboard layout of the host macOS system with the one in the sim, and apparently iOS can't change the keyboard layout without changing the language of the environment. So, tried unchecking the option I/O > Keyboard > Use the same Keyboard Language as macOS and lo and behold, the inconvenient behaviour stopped.
You can switch it back again when you need to input in your other language – that is a need I don't have in the simulator, so I'm leaving it permanently off.