@septer012 

There are not any current plans for a 4-way switch, however it may be possible that a HS210 3-way product may work in this enviroment.  It has not been test so before purchasing and attempting we would recomend contacting an electirican for assistance.  

each unit has a attached Neutral and Ground wire and 2 binding screws for the travelers and one binding screw for the common wire. Installation should be like a 3-way enviroment, where the HS210 would need to be installed in switch location that provides "power" to the 4-way run,  If its plugged into a Load.  Note you only need to replace 1 switch to add smart functionoality to the switch enviorment.  

Best Regards