I was installing a TP-link HS210 3-way smart switch in my dinning room. On the side with the mains power I do have a neutral wire, but on the other switch I have no neutral wire from the wall (for that breaker). I do have a switch that's on the kitchen breaker right next to it, though, and that has a neutral and ground.
In my breaker box, both the neutral and grounds appear to be on the same row of lugs.
Running the neutral wire from the switch to the ground works, and I'm thinking it's because it's all going to the same place. This specific switch didn't explicitly say to do this, but other switches I've installed did.
Now, I could run the switch's neutral to the neutral on the kitchen circuit. I didn't at first because I had the other switch wired wrong, so I thought it was the no neutral switch causing issues.