This is an interesting idea. But I think the reaction of other Protestant states would depend upon when we're talking about. Remember that Henry VIII was not a Protestant. When he made himself head of the Church of England, he did not do so out of any Protestant conviction, and his own writings on theology indicate that he always remained a Catholic in pretty much every respect apart from his attitude to the Pope and his headship of the church (admittedly a rather important point). It was his advisers and others who subsequently took the opportunity to use Henry's novel approach to church-state relations to usher in a quiet ecclesiastical, theological, and liturgical revolution along Protestant lines.
So my point is - if this Crusade were preached immediate after Henry's break with Rome, would the Protestant states regard Henry as an ally at all? They would probably think that anyone in trouble with the Pope was to be encouraged, on general principles, but I don't think they would regard themselves as theologically obliged to ally with him. Conversely, would the Catholic states see this as a religious matter? I don't know enough about this period to say, but I should think that, at least initially, they would regard this as a spat between a Catholic monarch and the Pope. And there's no guarantee that every Catholic state would necessarily support the Pope in this spat - after all, plenty of Catholic monarchs had had such spats in the past, and found plenty of allies in other Catholic monarchs. I suspect that if a Crusade were preached against England immediately after the Act of Supremacy, Henry might at least have the possibility of convincing some of his fellow Catholic monarchs that it was in their best interests to have a Catholic Church that answered to the monarch in each state, not to the foreign Pope. Perhaps he could build an alliance of his own, fighting for a sort of federalist Catholic Church instead of an ultramontane one. This could be, effectively, Gallicanism and Febronianism a hundred and fifty years early.
I don't know which, if any, Catholic states could be persuaded to go along with this (although I assume the French would be open to it) because, as I say, I don't know enough about this period. But it would be an interesting scenario. Among other things, if this did happen and Henry VIII and his allies were to present their war as a war for reform of the Catholic Church rather than as part of the Protestant movement, I should think it would mean that the Church of England would never become Protestant at all. Henry would not want any suggestion that his church were to be reformed along Lutheran lines, for fear of alienating his allies. If he lost the war, then, the Church of England would probably be re-absorbed back into the Catholic Church. If he won (or if he lost after a sufficiently long period), the relation between the Church of England and the Catholic Church might end up being rather like that between the Catholic and Orthodox churches today, but without the differences in practice and belief. And perhaps there would be similar autonomous Catholic churches throughout Europe if the same thing happened in the states allied to Henry.
But yeah, power-politically, I can't see France combining with the Habsburgs for any purpose, and if Henry successfully presents his program as a Catholic reform one like Plotinus thought (though admittedly this reduces the booty he can claim from plundered monasteries) the French might even be co-opted, and the war would simply take the course of yet another of the endless Italian Wars.
I thought England and France cultivated a similar hostility as it did with Germany. 
