As mentioned in a previous post, we had already replaced our battery charger (that only accepted 110V) with a new one from Sterling (that accepts 110V and 220V).
All that was missing was a physical connection to shore power in the US as well as in Europe. I therefore bought a European (blue) set of male and female connectors to install into an US shorepower cord (yellow).
Peter, our uber-electrician, finally put it all together. We spend some time figuring out neutral, ground and positive (for the US cable) and ground plus two hot (for the EU cable) to make sure the connections made sense. After that, Peter showed off his talent and put it all together with the usual precision.
I also bought a connector cable that allows us to connect to a regular central European outlet. With that we can now connect to US marine and shore as well as to EU marine and regular outlets.