Yes Russian economy had already fallen way behind since it became a centralised economy in 1917, who knows how they might have been with better rulers given all the resources available to them.
The british economy largely depended on imports from the empire and its manufacturing was in the hands of a wealthy minority. Once it had to pay world prices for materials the wealthy largely bailed out.
What it did have was a well educated middle class and technocrats which not only provided the science that developed innovative solutions Chain Home, cavity magnetron, Colossus amongst many others, details of which were freely given to US who benefited very well from the gift.
Despite the set back to the economy it remains a good place to live and work although Canada and Australia were tempting. The national insurance scheme actually means I would only spend 60% of my life earning 🙂 but that probably won't last for the next generation as the Gini ratio moves to the american way.
The answer is probably that there never would have been an invasion of europe; that depended on our half american prime minister persuading Roosevelt, to deal with Europe first while the bulk of the German army were engaged in Russia.
Japan made a fundemental mistake in attacking America when they did, this doomed Hitler.
Japan was in an onerous position, already embargoed by US and, like Britain dependent on imports. Their miscalculation was in thinking if they swept up all the colonial assets of the French, Dutch and British once Germany occupied mainland Europe , their main enemy now now occupied fighting germany for the las six months and with the incursion into China stalled, America would intervene. It would not have.
Eventually there would have been a war between Japan and US but too late to save Europe.
The axis were a dysfunctional alliance whereas America, Britain (which headed the commonwealth of nations, many still colonies) and Russia (less so) were coordinated.
The fly in Hitler's plan to create a reich which could out compete the american economy depended on the securing of land and resources in eastern europe, he thought he had settled a deception on Chamberlain
but 31 March 1939 Chamberlain had signed an agreement with France and Poland (which Russia was planning to invade) that they would come to their aid should Germany attack. German plans depended on taking Poland in order to get to their goal of the agricultural lands of Ukraine and the oil fields to the south of USSR.
When Hitler invaded Poland in September 1939 and Russia was given the east Poland two months later as a feint, Hitler did not expect Chamberlain to declare war. So he had to bring forward his contingency plan to attack France through the low countries.