Attention: In "island operation" (i.e. not connected to the house mains), the 230V output is a so-called IT mains (no clear phase/neutral conductor, protective conductor not looped through). If connected to the mains, the phase and neutral conductor are connected, including the protective conductor. But: Since the Schuko can be plugged in either way, there is a 50% probability that the neutral conductor and phase are reversed. This can be very dangerous if two faulty devices are connected. That is the reason why this is actually "forbidden" and why three out of four connections are blocked.

Yes, it works with an adapter from Max Hauri 16 A for Fr 8.90.
All 4 can be plugged in and used......have 4 devices running at the same time works perfectly.