Does anyone have a wiring diagram for the HS210? We did a remodel and installed all new TP Link smart switches. We added 3 way switches for one set of lights and have not been able to get them to work

I've been experimenting with the HS210 with a multimeter. I noticed when I don't have a load on either traveler that each leg has 120 volts when the manual switch is clicked. But the non powered side