Prussia vs Holy Rome:
German People vs German People, or Prussia vs Holy Roman Empire of Germany or Germany vs Austria

Hmms it seems a civil war to me
UU:
Panzer vs landsknecht:
Lansdknecht is way better in its era.
UB:
Assembly plant vs rathaus:
Rathaus is more useful for both.
UP:
Technic vs emperor:
Halved upgrades vs double voting in the apostolic palace. This double vote isn't so useful, except if you go for an early diplomacy victory.
Halved/free upgrades save a lot of valuable gold...
UHC1:
Berlin vs Crusades:
Crusades win.
UHC2:
Third Reich vs Protestantism:
Third Reich wins (for the moment).
UHC3:
Internet vs Vienna:
Internet wins.
Austria: 3
Prussia: 3
Draw.
Historicity:
HRE's history is represented well. You can see the crusades and the reformation, two events that had a global impact. I prefer the 3 european vassals as 3rd UHC than the 3 artists (Motzart, Bach and Vivaldi?).
Prussia's managed to conquer almost all of Europe making it is a really enjoyable game. However,
HRE impact is better.
The german people win! Well, I meant the Kingdom of Germany, oh..., ok the 1st german empire... It isn't clear either... The
Imperium Romanum Sacrum or modern
Österreich.
P.S: Since Prussia is easter than Austria, why Austria is called Österreich(=Eastern Empire)?