Livestream Studio includes the ability to change the language of the Studio interface between English and Chinese.
Click the gearwheel button in the upper right corner of the Studio interface. Navigate to the Settings: Advanced menu. Towards the bottom will be the Language dropdown menu where you can select your preferred language.
You will be notified that your language setting has changed. It will be applied when you relaunch Studio.
If you ever do this accidentally, click the gearwheel in the Studio interface. The third tab from the bottom left is the Advanced menu. The third setting from the bottom of the menu is the language dropdown menu; select English, press the blue Save button, and relaunch Studio. The interface will return to English.