But it takes two turns to arrive in WR. So first step is always Ukraine, being Belorussia an inferior choices. The final destination of the Gemran Army moving west is Moscow, passing for WR or Caucasus, depending on the situation. So it is not a different proposal from going to Ukraine, is a possible step after that move.
The problem that I see is that meanwhile Allies could invade Karelia and then EE.
Or, moving Karelia and Arcangelsk, being ready to counterattack in Moscow if it falls.
Moving German main army East implies redisposition of German Fig. further East, for being useful.
I thing that the German may efficiently focus on EE dead zoning Karelia and trading it every turn. If Allied come out in force, strafing them for at least delay their action. This should give to the Japanese all the needed time for conquering Moscow and for relieving Germany.