Probably not, if officially the Kingdom of Bohemia continued to exist and even Czech identity and language after all this time, and that area was surrounded by Germans even to where official Bohemian territory became Germanized (German-Bohemia, the Sudetenland) but not the core. And if Germans didn't make Czechia German, well....
Habsburgs were always big on local rights and traditions to make it easier for them to be the overall lord, so even if they TOOK Venice, it'll undoubtedly keep its identity. Especially when one considers Venice had a long, proud, and conscious history and culture up to and beyond the 1400s in OTL.