IVORY 3-way smart-switch for dusk/dawn timer?

The ZEN76 switch with a light almond paddle replacement will work but you need a physical SmartThings (or Aeotec) hub to control it remotely since it’s a Z-Wave device. You only need 1 ZEN76 switch and you can keep your existing 3-way switch on the other side of the 3-way to make the whole set-up smart.