To apply this to your current installation, you may need to Photoshop from within the Creative Cloud app. Manual File Method (Advanced)
If the German language pack is already installed on your system but not active, you can switch it within the software: Go to > Preferences > Interface . Under UI Language , look for Deutsch in the dropdown menu. Restart Photoshop to apply the changes. Manual Installation (Legacy/Standalone)
: Place the downloaded de_DE folder into the Locales directory.