There are currently no language option in the game itself for the beta, but there is a way to choose different languages through the use of launch commands!
Guide to Change Language of the Game Interface
- Open the Library, then Right Click on the Payday 3 BETA game and select Properties.
- Click on the Set Launch Options button.
- Write -language=xx-XX argument in the text field, then click OK.
The languages are followed:
In new version of the steam interface has become even easier.