I have an exterior light that has 2 14/2 cables - one is line + neutral from the panel and the other goes to a wall switch inside the house (effectively a line+load). The neutral from the panel and the white leg of the wall switch cable are connected to the light, and the black leg of the wall switch cable is connected to the hot line from the panel.
I’d like to replace the switch with a smart switch and it would be nice not to have to pull new cables. The best I can come up with is doing a 3 way junction of neutrals and a 3 way junction of hot lines at the light to power the light fixture all the time and have a line/neutral at the wall switch. I’d put a smart bulb in the fixture and a smart switch in the wall. Then I’d just need to add some automations to get the bulb to turn on/off with the switch.
With the smart lighting app it should function during ST outages, but I’m not sure about safety / best practice or if there is a simpler solution that I haven’t thought of.