Let's say that it happens right after the Austrian defeat to Prussia, the Hungarians don't want cooperation and instead rebel against the monarchy. My take is:
Austria-Bohemia-Slovenia: Probably would go for Germany if Germany still is unified some years later as OTL.
Galicia-Lodomeria: Hungary probably wants it but can't get it, Russia also wants it, there is a chance of being kept by the Habsburgs in some form if the Habsburgs are denied entrance in Germany, but I doubt it, probably goes to Russia.
Slovakia: Goes to Hungary, simply.
Transilvania: Goes to Hungary initially, but the Romanians want it and probably are willing to make war for it.
Banat and Croatia: Goes to Hungary, but they are going to rebel immediately, Serbia will fight for those territories right away and probably will win.
Results:
Assuming that Prussia still unifies it will have many more Catholics to deal inside Germany, and the south Germans can rally under the leadership of Bavaria and Austria defeating completely the Bismarckian goal of a united Germany under the sole leadership of Prussia.
If Russia takes Galicia, they need to deal with a lot of Polish and Ruthenian people that are used to be "too free" for Russian tastes, not only that but I think that Britain and Germany are going to form an alliance against Russia. All the Balkans will fall into the Russia sphere of influence.
I think that Hungary is going to lose Croatia, Banat and Transylvania.
Maybe WW1 happens earlier as an escalation of another Russo-Ottoman war.
In the end I think that the biggest beneficiaries in TTL are the Romanians and the Bavarians (seriously), maybe the Serbians too if they can keep their new Yugoslavia together.
so possibly not too much local resistance.
The Polish want to be part of Poland, but not a Russian Poland, I don't know if they are going stage a revolt, but at least they are going to sulk a lot...