Why is that particularly bad necessarily for Italy? France vs Austria works okay. Remember Italy was largely unified OTL when a unified Germany was still no more than a twinkle in Bismarck's eye. Germany made it easier to get Rome and Venetia, but the former was probably going to happen eventually and the latter would make Italy very salty, but isn't essential.
There's also the fact that without Napoleon, Austria may not be able to gobble up Venice.