The map above shows Austria (or as it was called at the time the Empire of Austria, or the Empire of Austro-Hungary) in Gray, yes a bit bigger but this is a map from around 1918. Transylvania borders Romania, and At certain points, Germany and Russia. ( Before 1918, the Ukraine was a part of Russia and Poland was divided between Imperial Germany and Russia, Transylvania was a part of the dual Monarchy.)
I wonder though one thing, Crown Prince Rudolf of Austria and Hungary was more liberal than his father and would have ruled Austria had he not committed suicide before his father's death. Here is an interesting link between the Crown Princess of Austria, Stephanie, and Queen Marie of Romania, they were distant cousins. Also, had Archduke Franz Ferdinand not been shot to begin the Great War, it might have turned out that Transylvania would still be a part of Hungary.