I'm trying to replace an electrical switch (controlling a whole house fan in attic that should only run when the downstairs windows are open to not suck air from the chimney) with an Insteon switch that can be controlled by Insteon controls (smartphone app/amazon echo). (It's currently annoying as before bed, I hang out downstairs, have to walk to the attic, turn off the fan, walk downstairs, close the windows, and then go to bed and would be nice to turn off from downstairs.)
However, the switch for the fan is wired Supply -> Fixture -> Switch aka what is described as the "standard black-white setup" and with the images where wires are "coded black" here, where there are just two wires going into the switch a black wire and a white wire painted black at the end. The Insteon device needs a neutral and ground, which do not seem to be present.
Could someone verify that I (or an electrician) needs to run new wires between the supply and the switch and then back to the fan, putting the switch between the supply and the fixture? Or more specifically, there isn't another type of programmable switch that could work in this setup without rewiring (and preferably is compatible with Insteon hub and/or amazon echo)?