- All of the errors are as expected (I should probably capture/isolate the 2nd to last error).
- It should not be the dual drivers - but change the driver for your HS 110 (go to the device's page and near the bottom you can select the type (driver).
- You are getting no indication that Hubitat is turning the devices on / off. so I do not think it is the Hubitat end. Kasa App????? Question would be, does the Kasa App show the correct state.
- Have you tried rebooting the HS300 (unplug, plug back in in 15 seconds). There is some quirkiness in the TP-Link Firmware.
Out of curiosity, go to the Kasa App and get the firmware version for your HS 300. TP-Link has been working on SmartThings integration and they may have had to change the firmware.
I am currently out-of-pocket, but in a couple of days I might be able to run some tests.