On Windows, game language option (right click on game/Settings/Language/Select a language) controlled only the language used in audio files, but the text in this game is always displayed using Steam client's language setting (at least for Valve's games). So, if user selects English for TF2 and Russian for Steam client, voice acting in TF2 will be English, and text strings will be in Russian.
On Linux, game language option sets language for both audio and text.
On Windows, game language option (right click on game/Settings/Language/Select a language) controlled only the language used in audio files, but the text in this game is always displayed using Steam client's language setting (at least for Valve's games). So, if user selects English for TF2 and Russian for Steam client, voice acting in TF2 will be English, and text strings will be in Russian.
On Linux, game language option sets language for both audio and text.