Run the Sims.Language.Selector.exe as an administrator.
Go to Game Properties > Advanced Launch Options and select your language from the dropdown menu. 3DMGAME-The-Sims-4-Language-Selector-Xuanze-Tools
Copy the executable and supporting files into your main The Sims 4 installation folder. Run the Sims
This tool was originally released on the Chinese gaming forum to bypass the tedious process of reinstalling the entire game just to change its display language. It works by modifying the game's configuration files and registry entries to force the application to load specific language assets. Key features include: 3DMGAME-The-Sims-4-Language-Selector-Xuanze-Tools
Often distributed as a small executable that runs directly from the game directory. How to Use the Language Selector