Though it’s possible that NATO HQ might be moved to the United Kingdom, it’s totally unrealistic that they would have it in Ireland(since the Irish Republic was never part of NATO, and would never even join NATO in that timeline). As per having NATO based out of Northern Ireland, I could just imagine the complications that would occur during the troubles...
More than likely though, SHAPE will still end up in Brussels, and there still will be the French split in NATO.
Sorry about Irland, forgott to look on the NATO members, with expansion of NATO I lost the overview...
On HQ Paris and later Brussels were chosen because there distance to East Germany
with West Germany between as Buffer and combatzone
but here is Germany total a Sovjet zone of occupation (SZO)
so Brussel 125 km from SZO OTL 325 km from DDR, while Paris was 620 Km away from DDR
and Paris in this TL 315 km, London is 460 km from SZO
How deal Stalin with Remains of Thrid Reich ?
IMHO He make simerlar change like in OTL:
Move Poland to west, separate Austria from Germany
but still give a Germany in size ot Today, wat is not a Option for Stalin
there two way for him to deal with this:
deportations of milions Germans to east of Soviet Union. so to thin out the population.
partitioning the SOZ in several zones, were inhabitant are restricted to leave.
by the way, the Red Army occupation of Germany & Austria
will cost far more as OTL DDR roughly 4 time more
give this the opportunity that Soviet Union collaps earlier ?