We did win, in the long term; the UK is the largest economy in Europe and we lead the European Federation in all but name.
Not really, more like running it from Boston or New York.Best explanation I've ever seen for how useless the Federation is. Running Europe from London is like running North America from Greenland.
Mosley would have to halt his ridiculous persecution of the Irish for that not to happen, and I don't think we'll see that.
You could always have Mosley avoid being shot in the arm by that Irishman in the Somme, or simply have his attempts to cover up his Irish ancestry fail. With no reason to hate the Irish Mosley wouldn't bother invading in 1935 and would have an extra 200,000 men to attack Germany with rather than subduing Irishmen for the duration of the war.
This could very easily be done by having Britain win the battle of Paris. They very nearly pulled it off.