Yes, they are setup when you link the harmony app to ST via Logitech Harmony (connect) app. They are active switches with status reporting from harmony, the ONLY reason to add the switch into the harmony activity is to speed up reporting back to ST, particularly if you want ST automations triggered off harmony activities (i.e. I have tv LED backlighting that adjusts brightness based upon TV status / time of day)
I take no credit in figuring this out, see below thread: