Set the Crossover GUI to use a different language than the OS
Crossover translates its menus and tools into multiple languages by recognizing your OS language settings. If you'd like Crossover's menus and tools (*just* Crossover, not windows apps *in* Crossover) set to a different language than your OS, open up a terminal (Applications>Utilities>Terminal) and enter
defaults write com.codeweavers.CrossOver AppleLanguages -array en
The above example sets Crossover to run in English. The "en" variable is where you should put the language setting.