[lsaferite]

I use Insteon for all of the switches and fans in my house. Those are combined with an isy99 for automation. My thermostat is a Venstar T7900 which is WiFi connected, but doesn't need to connect to the internet and has a local API that can link into the rest of my HA setup. My home security system has a local network interface via an EyezOn module for integrating all of those sensors into the HA system. I also have an RPi running Home Assistant for tying a lot of these things together.

None of this _requires_ an external network connection. I have a hard rule that my automation needs to operate without a connection to the outside world.

That being said, I can easily connect this setup to Google Home or Alexa to add in voice control (which I have done). If a viable offline voice assistant comes along I'll 100% add that to my local setup.