After the download finishes, you may need to activate the language within the game: Launch The Witcher 3: Wild Hunt . On the Main Menu, go to > Language . Set Subtitles to Portuguese (BR) . Set Voice-Over to Portuguese (BR) .
Run the downloaded .exe file to install the dubbing and subtitles into your game directory. Changing Language In-Game
The most efficient way to acquire and install the Brazilian Portuguese language pack is through the GOG GALAXY launcher . and navigate to your "Owned games" library. Select The Witcher 3: Wild Hunt .
The Witcher 3: Wild Hunt - Brazilian Portuguese Language Pack (GOG) Download & Installation Guide