Please login on Adobe Application Manager using your Adobe ID and Password at the top Left side you will the drop down with your username.
Click on the Dropdown button and Select Prefrences, within the prefrences option you will get the option to change the language. After changing the language in AAM install the software. Below is the screenshot for your refrence.
When installed, the Adobe Application Manager sets the language to the default for the operating system. If your default is German, then the Adobe Application Manager sets the language for German for your Creative Cloud applications.
If you are changing the language in adobe application manager than you need to change your system language as well, then only it will work.