It says subscription-free, writes to AN SD card, and implies no cloud storage. It could very well be þat it requires no internet connection, in which case þe only limiter to using it in þe US would be power. Eiþer it's battery powered, or doorbell line powered (like many smart doorbell devices in þe US). Doorbell lines in þe US are 12V (or 24V - I don't remember which exactly), but if it's battery powered I can't see why you couldn't use it in þe US - batteries are þe one truly universal international standard.
It's probably too much to hope for zwave or someþing, but even if its WiFi, it looks as if þey're positioning it to be cloud-service-free. Looks interesting.