I've got a 7a International version and 5G works in my unsupported country (New Zealand). Not sure what other unique features don't work.
However it is nuts how they just can't be bothered supporting so many countries.
It's disabled geographically, not based on band compatibility or carrier or anything. Not sure about New Zealand because I heard it's not consistent.
It'd be 5G, VoLTE/Wifi, VPN, call screening, OTP autodelete, crash detection.
If you buy it in a country that's not officially supported you don't get 5G, most unique features, and of course no warranty, support, or repairs.