@Glennen_81
Well, it depends on the specific game.
I am a German living in Germany, and I could play Mass Effect 3 in German and also in English right from the start. (changing the language is done in game.) The game came with multiple accessible languages out of the box.
In DA I the English language pack is accessible via "extra content" section inside the DA I menu as a downloadable language pack.
Andromeda is fully German localised, but the international version that is sold in Germany also supports English.
So if BW is not changing there Politics completely you will be able to change the language to English at one or the other way. (my money is on the ME3 method.)
If you want to be absolutely sure wait until the Origin access trial starts, that is on March 16, then you will get 100% conformation if you can change the language in game.
For "The Saboteur"
There can be multiple reasons why a game don't has the English languages version available, in the case of the "The Saboteur" it could be that the German key you presumably bought lock's the languages to German because the game is censored in Germany. But that is just an assumption.