Again, that's not how it works. In your example, player who has German localization will hear "Es geht loss!" while player who has International localization will hear "Keep em coming!". Same goes with the PT example. International localization will keep it English for the corresponding clients while clients with other localization will translate it according to the client's localization
Of course, it all depends on the UI and such. If it's set to English in... say the SWF file, then nothing can be done to it
We can also establish that World of Warcraft does not use Unreal Engine 3's language systems
But yes, as I said, chatting from players are still going to be in the same.