Do you enable remote control for the HS200? Go to Device Settings to make sure remote control is switched on.

Thanks for the response.
Yes, remote control is and has been enabled. Despite that, it shows "Local Only." My smart outlets do not have this issue. I can control those remotely, but not the HS200.

I found one of my devices in a similar situation - remote control marked as on but it wasn't working properly. Trying to toggle the remote switch caused some odd behavior as well. It was sorted by resetting then adding it back into Kasa (after making sure I was logged into my account). I can't verify but I suspect some things were messed up during the last Kasa update when I was (we all were?) logged out of the cloud servers.

Thanks, Mike! That addressed the problem. I reset the switch via the reset button, and added it back to Kasa, and "Local Only" is no longer displayed! I verified that it works by turning WiFi off on my phone, and the HS200 remains active using a cellular connection.