(Apologies since this has been asked before, but I can't seem to decipher other answers)
I have a 3 way switch in my garage for overheard fluorescent lights. S1 is in a single gang box with no other wiring, S2 is in a 2 gang box with another independent light switch. I'd like to re-wire the 3-way with a tp-link smart switch (that requires a neutral) but from what I can tell (confirmed with a multi-meter) I do not have a neutral in S1. The wiring fits the image below, which has been referred to as a power-in-fixture installation.
S1 (top left) has a ground, a white always-hot wire, 2 travelers, no neutral, nothing else in the box. S2 has a ground, no always-hot wires (Though the other switch in box 2 has a hot wire), 2 travelers, and the load wire.
What are my options to get this to support a smart 3-way switch that requires a neutral? I've read about using the ground as a neutral but It's almost always cited as a bad idea.
I realize there are smart switches that do not require neutrals, but I've already bought a specific brand and installed them in the rest of the house and If possible I'd like to avoid dealing with multiple manufacturers and control apps.
Edit: I came up with an acceptable work-around. The 2-gang box has a neutral, so I can use the smart switch there, and I can leave a normal 3-way toggle switch at the single gang box. The 3-way smart switch works just as well being one-half of the circuit. So really the only difference is that the other switch is a toggle instead of an aesthetically matching paddle switch, but I think I can live with that for now. I'd still be interested in any tips that would allow me to replace the switch in the single gang box as well though.