We automatically took over the specification "Telekom/congstar" from our purchasing department. After consulting with our supplier, I was able to find out that the article should work regardless of the country, even in Switzerland.

The thing works wonderfully with 5G. At least with a Swisscom SIM I had good speeds. On the Sunrise network it was probably "only" 5G NSA, so not quite as fast. But that could also be due to my location

"... Article should work regardless of country" does not mean that this device has been configured for 5G on the CH networks. Could you please clarify whether the device is approved for 5G on our networks?
With smartphones, it happens time and again that they can use 5G but are not configured for our networks.