No, out-of-the-box the U200 is not compatible with Swiss round cylinders and, according to Aqara, no adapter is planned. KABA round cylinders have a 22mm diameter while DIN-EN profile cylinders have a diameter of 17mm. This means that the KABA cylinder does not fit into the hole in the adapter plate of the U200.

As you have already mentioned, the Aqara Smart Lock U200 is compatible with European and American door locks according to the manufacturer's website. Swiss door locks generally comply with the European standard, in particular the profile cylinder lock (DIN standard), which is also used in many other European countries. It is therefore very likely that the Aqara Smart Lock U200 is also compatible with Swiss door locks as long as they comply with the European standard.

For absolute security, however, it should be checked whether the specific door lock in Switzerland complies with the European profile cylinder lock standard (DIN). If in doubt, the manufacturer's customer support can help to ensure compatibility. At least it fits my lock perfectly.