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.
I'll offer some more clarity on why swapping neutral and ground is bad. In North American electrical code parlance, the issue is known as "objectionable current" and is a result of electricity taking all available paths back to its source. Basically, while neutral and ground wires go back to the same place, putting current onto the ground wire means developing a voltage -- due to Ohm's Law -- and that presents a shock hazard for any upstream or downstream outlet's ground.
Imagine that downstream is a refrigerator or computer, where you get a minor shock just by touching the exterior metal case. This is very bad.
We do not want any voltage across the ground wire, so that requires that we must not intentionally put current through the ground wire. Ohm's Law is unrelenting here.