> If you do not have a Xiaomi central hub gateway or other devices having central hub gateway function, all control commands are sent through Xiaomi Cloud.

Now I don't actually know what central hub gateway function entails :) but it does sound like some non-Xiaomi devices could also fulfill this role.

In case of HASS I think local network is a pretty decent assumption. I have my HASS on both my local VLAN as well as the IOT VLAN.