This use case gets brought up every couple of months, and the shortest answer is that there are devices designed to do exactly this, they work well, and you won’t have to worry about smartthings involvement at all. 
Essentially they are Wi-Fi pocket sockets that ping (either a company selected website or one of your choice, depending on the brand) and if that ping doesn’t succeed, the pocketsocket reboots itself.
Like I said, these are simple, they work well, lots of community members have used them.
There are several different brands. Some only allow for one device to be plugged into them, some allow for two or three, costs vary.
See the following post from last year for specifics: