I wanted to install Rainbow 6 Siege today, but during installation process I was unable to select Polish and English languages at the same time. Personally I like to play the game in English but because my friends speak polish it's easier for me to switch languages when I play with them and know how are the map spots named in polish.
Hello Zeegaar, thank you for posting.
If you select to install the English language, you should be able to access Menu and Subtitle language in the games Audio settings menu, but you will only be able to select English Audio for now. This should be the case if you own the european version of the game.