As much as this topic is repeating itself the answer will repeat itself over and over again aswell.
There wont be a cold war expansion, simple as that. Podcat himself even confirmed that, since that would require a complete rework of the existing gameplay mechanics, which is completly out of scope of an expansion. There is a reason why CK, EU, VIC and HoI are seperate games instead of one big game running for almost 1200 years. Simply tacking on a cold war scenario simply wouldnt fit in and would feel misplaced, since basicly none of the political struggle could be reflected propperly, just as with an ww1 expansion.
Stuff like operation unthinkable can already be done in the vanilla game, since there is no hardcoded end and some of the tech trees also go on until 1950.
Podcat also mentioned that he thinks a korean war expansion could work, but did not say or deny that they will ever do one, to be clear.
Q: What is the planned end date for the game. Also are there any plans for extending the end date via dlc or something?
A: you get a score screen in 1948 but can keep playing. Time extensions are not impossible but a full cold war game is not realistic to be built on something so war focused as HOI. Korea etc is within reason tho.
As for the EvW part, you probably should read the forum rules.
Threads discussing East versus West will not be started, nor should members of the community request cannibalization of East versus West's programming for inclusion in Hearts of Iron IV. Threads engaging in this behavior will be closed