I was wondering why Maria would give up Silesia so readily. It really is too much to ask, but for the sake of the game, I'll play along . There's really only France and Russia who might attack Austria. Russia was busy with Sweden, and pro Austria, at the time, so you have to avoid that if you want them to be the instigator. That leaves France. they could, as the did OTL, get the Spanish involved, and a few minor powers, such as Bavaria. Although France participated OTL for a few years without declaring war, it's hard to see them as aggressors without a declaration ATL. (edit: I suppose it's possible France could incite Bavaria to be the aggressor and not officially declare war, but I don't see a minor power getting pushed into starting the war without full fledged support). England likely declares war, too, so you have France, Bavaria, and Spain (all who were fairly inept militarily about that time) vs England, Prussia, Austria and an assortment of minor powers. France/Spain have the edge in the navy, and if they were smart, they'd go for a England first policy, but OTL, they were a Austria first policy, and since they start the war against Austria, you have to assume they combine the navies to hold their own on the seas while pursuing a continental military aggression. A second smart thing would be to take Minorca, but Spain under Farnese was too intent on capturing Italian lands than reclaiming Minorca. No reason to see a change in policy there, and France isn't going to push for it if they can't use it as a bargaining chip. You likely see France, Bavaria, Spain flounder as they did OTL, at best. With Prussia against them, they might lose some major battles. Britain likely takes Louisbourg, and possibly more. All around, I see Austria, Prussia, England winning this war rather handily. But, while not technically ASB, it is far fetched. Austria would easily blunt F,B,S just as they did OTL, and have no reason to give in to Prussia. Frederick would sieze the opportunity to take Silesia and then bow out of the war, just as he did OTL. If, for some strange reason Austria did give up Silesia, Frederick would not go gung ho vs France, but do just enough just long enough until Austria vacates Silesia, then he drops out, and we have pretty much OTL war.