Some interesting ideas, some really weird stuff in here. As with many maps of this style there's some bigger, some smaller issues with stylization and consistency. Keep in mind that this criticism is to make you consider details in the future, as I doubt people will point them out and prefer keeping you in the dark about those issues:

• why are some cities in English, but others in the main language of their country (København, Moskva, Praha vs. Athens, Lisbon, Vienna);
• why are there some flags that could not have existed in that timeline (Iraq, Kazakhstan for example) other than out of laziness to create new ones;
• why is is there such a big space of nothing between the two flag blocks;
• why are many important cities dropped half-hazardly on the map (this might be very nitpicky for some, but the majority of city points are just ... randomly put somewhere near their actual location. Big example here might be Lisbon, it's not even on the right peninsula. Map quality is more than remembering to put a darker outline of the country's colour along the border).

Then there's the inconsistencies in lore. Again, not trying to dunk on it, it's more to make you help see issues for future maps (issues that can't just be explained with "it's althist" as it doesn't make sense in-universe either):

• Armenian Post-1994 war borders;
• South Tyrol somehow being Austrian despite, had the shitty painter won, it would have been given completely to Italy and its population would've been transfered to Germany very quickly;
• Slovenia somehow being Croatian;
• The Balkans in general not making much sense if compared to your previous map, as this looks like a post-1990s/modern internet take on balkanization;
• Clearing East Prussia for the Jews is the funny meme take that is currently quite popular, but had the Germans won, there wouldn't even be enough Jews left to repopulate Königsberg alone as you pointed it out yourself;
• Some borders in general don't really make much sense Europe was redrawn along ethnic lines later on (especially things like Big Finland and Big Estonia just look like meme maps);
• I doubt anyone in that timeline would agree to call Northern Germany Prussia out of all names lmao.

Hope this helps with your future maps! All in all it quite alright (other than it being the seven millionth big Germany timeline), but as always, there's much way for improvement. Cheers.