Not very easily, from what I know. For a start, they were all committed members of the Hanseatic League, which was both very profitable for them most of the time, and was the lifeblood of their trade. Where cities further west slowly divorced themselves from the Hansa in order to promote local trade, for those German states, the Hansa trade was the local trade. I'm not sure they had the infrastructure or human resources to switch to the colonial trade. Secondly there's the problem that the Netherlands was formed from sizable states, with a universal interest in politics, military defence etc, and the population to act on it. The German trading states were very small, almost entirely urbanised, with different political interests depending on their location and no way of defending each other, really, except perhaps from by sea...which would be no use at all since all of their threats would come from inland. These states tended instead to rely on their money to buy off threats, and still had to contend with local larger states picking on them for profit. There would be little logic for unification, they would be more of a liability to each other than a help - for instance imagine if Portugal was to somehow unite with Venice, and then each country keep dragging the other into wars on the other side of Europe from the other. There's also the problem that the Netherlands were very defensible in a pinch - when you can flood an entire country and turn strategic cities into literal islands, you can survive most things, albeit at huge cost. The German cities could not do that. If they tried to unite, either they'd get in trouble with the HRE if they tried to assert independence, or they'd get attacked by jealous neighbours wanting a trading capital to enrich their own state. Under such events, their cities would fall soon enough. Those are the main problems. There's a few other things, but they're more petty so I won't touch on them.