WI Stalin and Beria die (by nature, by their own hands or with assistance) in the immediate aftermath of June 22nd 1941.
Assuming Zukov does as well as he did in OTL in the next year or so he would be incredibly influentual whoever ends up head of the official government,
I am assuming that he would not want the risk of a further war after what had happened to his country.
So he is prepared to do a deal with the exile government to as it were 'Finlandize' Poland.
Soviet forces therefore give aid to the Warsaw uprising and are perhaps able to arrange relief.
(By the way does this get Soviet troops in Berlin sooner)
Poland has freeish elections but the government feels contrained to do nothing to annoy the Russians too much.
Nobody in the West minds all that much about what happens to the Nazi's minor allies (except Finland which goes as in OTL)
Czecholsovakia in OTL actually gave victory in pretty honest elections to Communists in the immediate aftermath of WW2, but they then arranged a coupe when they thougth they would lose. I think the 1948 coup would be avoided.
So what happens to Germany. In OTL there were some trials and some efforts and de-nazification. Very quickly both sides were willing to forget the history of useful scientists and intelligence folk(read tortuerers).
If the West and the Soviet Union were not so hostile how extensive would denazification have been?
If it were pursued seriously would the 'weirwolf' idea of a resistence to the occupiers in Germany have happened?
When, if at all, would any part of Germany be trusted to choose its own government?
Also what about Austria. In OTL although in fact deeply implicated in the Nazi system Austria managed to play 'first victim'. Would this happen?