Europe does not exist in the relevant sense. Germany does not exist in the relevant sense which is why this is so hard. Start up ecosystems are highly localized, like any other knowledge worker employer ecosystem. Silicon Valley managed to spill over as far as San Francisco and the rest of the Bay Area. LA is as tightly coupled to that ecosystem as Boston, New York or Montreal. You can’t evenly divide an ecosystem. In the EU it looks like Berlin might have one, maybe. Europe won’t. The closest you could get would be a border spanning metro area, like Aachen or Strasbourg.