Right-click on Hearts of Iron IV and select Properties .
Change the text inside the quotes to your desired language code. Here are the common codes:
Close HOI4 → Edit language= in Documents\Paradox Interactive\Hearts of Iron IV\settings.txt → Save → Restart. how to change language in hoi4
Save the file (Ctrl+S) and close Notepad.
Open the settings.txt file with a text editor (like Notepad). Right-click on Hearts of Iron IV and select Properties
(If you cannot find it, paste %USERPROFILE%\Documents\Paradox Interactive\Hearts of Iron IV\ into the address bar.)
Find the line that says: language="l_english" how to change language in hoi4
Close Hearts of Iron IV completely.