How can I configure my wireless power switches to default to on after power outage?

The manufacturer came back to me as follows:

Hello,

Thank you for reaching out to our support team. Unfortunately, there is not a programmable way to do this. The person in the video has modified his outlet to be able to have the light power on as soon as it is plugged into the outlet.

Please feel free to reach out to us if you have any further questions or concerns. We hope you enjoy the rest of your day.

Anyway, it is clear from the manufacturer that the wireless plug cannot do what is in the video.So all the claims from interpreting the manual that it can, is false.

I have no personal experience with ETEKCITY. However, based on a quick, non-scientific, perusal of their web site, I get the sense of "pretty web page selling cheap junk". Not that I am against cheap junk per se - I often go that direction myself, for certain products. But for controlling 120V equipment, I tend to prefer the better stuff. The rules are a bit different (for good reason) for devices hardwired to your electrical system, and, partly as a result of the R&D and testing required, they tend to be more long-term feature complete, reliable and seguro.

I would look at Leviton or Lutron or another manufacturer that specializes in electrical equipment, not a catch-all "USB mag-stripe reader, blood pressure monitor, digital scale, back massager, air mattress, etc." company that happens to have some WiFi controlled plugs too. (I have no problem with a retailer (online or bricks 'n mortar) that sells "everything under the sun". But a manufacturer can't possibly specialize in everything.)

Then you can check the online manuals and if they don't have enough details you have a reasonable hope of contacting someone who can answer your specific questions.