Installed 5 smart dimmer switches and 2 smart plugs and randomly they will all flicker at once (even the plugs). Just a few times a day I've noticed. But i also dont keep them on all day either. I have other equipment in the same room (ceiling fan w/ light and tv and other items not tied to these switches/plugs and they dont flicker or shut off or anything when the TP-link/kasa items flicker.
I've pulled them out again and rechecked the wiring and it all seems fine. I do have a bunch of random bulbs into the light fixtures so I don't know if that has anything to do with it. I plan on getting some LED dimmable ones. But would that explain the smart plug flickering too? The smart plugs only have a wax scent thingy and a light up tree