Mod Translation

FAQ: German for Deutsche and Russian for Soviets?
Unfortunately, there is no easy way to do it.
That does NOT mean it is not possible. (well, everything is possible)

Here is how it works. You will find all voice files under:
Company of Heroes 2\CoH2\Archives

Sound files are for everything like guns, blast etc.
Sound-Speech files are for dialogues, for Ardennes, Campaign, Theater of War, WFA & Vanilla Armies
if you use this guide, you can see English and German at the same time.

Problem: The voice pack of Vanilla/WFA armiesis merged into a single one, which means, Soviet+Ostheer is one file, OKW+USA is another.
You can have one speech for each package, ie: OKW and USA speaks English/Russian/whatever you want while Vanilla speaks German.
But not Soviet speaks Russian while Ostheer speaks German.

And of course, that also applies for campaign and stuff mentioned above. You can change the Soviet campaign voices into Russian & Ardennes in English (satisfy half your wish I guess), while leaving Multiplayer in German. But that's the limitation of the easy way.

Possibility:
Unless you can unpack it yourself and repack everything you want, the editor should be available with the modding tool, but it will be incredibly complicated and time-consuming for everyone.

And No. I can't do that for you because I'm not a programmer and I'm satisfied with funny Russians speaking German XD