Perhaps Kremlingames/Nostalgames might be of interest? Their first games was titled Crisis in the Kremlin. It allows you to guide the soviet union and create and live through alternative realities (what if the USSR had turned trotskyist?, what if OGAS succeeded?, what if the soviet union hadn’t left Afghanistan?, what if things escalated to direct armed/nuked confrontation, etc). It is however quite an unintuitive game and you would probably need a guide to play it. They are currently working on a sequel, though (Crisis in the Kremlin: The Cold War). However, they have newer games. One of them being China: Mao’s Legacy, which I think with the Fallen Eagle DLC, based on the reviews, allows you among other things lead to the collapse of NATO, but I haven’t played that game yet.
Ostalgie is indeed mostly about surviving or preventing the collapse of the socialist block (and Collapse: A Political Simulator is about the aftermath of the collapse), but in crisis of the kremlin, although very difficult, you can bring forth the collapse of the US. (I still don’t really play it, because I find the game difficult to understand and some things seemingly make no sense, that’s why I anxiously await the sequel). I still haven’t looked at China’s: Mao’s Legacy (as I think I should study the subject some more before trying it), so I don’t know how much you can kick the US in the balls with the DLC.
But yeah none of those games are grand-strategy wargames.