I have an x10 system in part of my home that controls outlets that are on separate circuits from the wall x10 wall switches. I would like to put wifi outlet plugs in the existing outlets (removing the x10 receivers) and replace the wall x10 transmitter switches with wifi switches. This would allow me to control the outlets with voice, phone, or the wall switch. I have only found 1 wall mounted wifi switch/controller that will control wifi outlets- the Leviton DW4BC-1BW. Unfortunately they run nearly $100 each. I would need 8 of them, so ouch. Anyone aware of a similarly functioning product, maybe something from China, that would be cheaper? Thanks!
SonOff has "Smart Wall Switches" that can be used as you describe and is also powered by mains.
They can also be re-programmable with other firmware like tasmota or with your own code as it is a ESP8266 MCU inside the device.
I have two "TX Series" that I have loaded Tasmota firmware on and that I have configure it to send the state of the buttons to a MQTT broker.
Then I have Node-Red and it is doing the logic control like: if button is pressed then do send toggle state to wallswitch.
The MQTT broker (mosquitto) is then sending the commands to the SonOff devices that is controlling light bulbs and blinds.
So the "TX Series" is the one I am referring to.