The Steam versions of Fallout 1, Fallout 2, and Fallout Tactics titles may encounter an issue with changing the in-game language.
Even if both the Boosteroid and Steam interfaces are set to the desired language, the game will have the English language installed. To fix this issue, please change the game language in its properties to any other one, and then return the value back to your desired language. These actions will force Steam to download the correct language files for the games. You can stick to our general guide on how to change the game language for Steam games below.