I didn't see anything either with a quick look.

Not sure if this would fit into your outlet box, but there are "contact modules" that are 20A. You probably would have to have a double gang box with a blanking plate over the controller.

https://www.amazon.com/LINEAR-FS20Z-1-Isolated-Contact-Fixture/dp/B00EPTMFH8/ref=sr_1_58?ie=UTF8&qid=1500953560&sr=8-58&keywords=z-wave+outlet

This looks similar to what I am thinking you would do. https://community.smartthings.com/t/garage-zwave-relay-switch/1176