Tp Link Kasa 3 way switch wiring assistance needed

I have a new home and have an electrician coming to install several tp link kasa 3 way and single pole smart switches. I just realized there’s actually a 3rd switch that controls the living room lights. Will my 3 way switches work? Is there something else I need to buy to ensure I can control my living room lights through ST integration? Currently I have 2 3way switches for him to install but I’m confused what to do with the 3rd switch.
Thank you