Create a Hubitat virtual motion or virtual contact sensor. Expose it to Alexa (i.e add it to the Amazon Alexa Skill).
Create Alexa routines that control the Alexa-controlled device of your choice using the state of the Hubitat virtual device as trigger (contact open/closed, motion active/inactive).
Use Hubitat automations to control the state of the virtual device.
Kasa devices are a special case. @djgutheinz has written a TP-Link integration for Hubitat that permits these devices to be controlled locally. I would recommend you use it.
I see ... while the procedure is complex with routines affecting routines, im just glad hubitat is flexible enuf to achieve this stuff w/ workarounds. Good good.