So in the joint Austro-Russian war with the Ottomans between 1787 and 1792, both the Austrians and the Russians were forced to end their wars early and cut their winning short (very short in the case of Austria) due to Prussian sabre rattling.
So what if the Austrians and Russians ignore Frederick William II's threats. Does Prussia actually enter the war?
If so what was the disposition of forces? The Austrian army of the period is qualitatively in peak form (although Laudon has kicked the bucket by this point), and the Russians have no less a man than Suvorov commanding their armies, where as the Prussians have the Duke of Brunswick as their top general.
If not (or if Prussia proves to be impotent) what would post-war Europe look like?