This is the simplest NES wall mount that I could come up with but I uploaded it to help other people save the 15 minutes of their life that it took to design it. It is mounted with two screws per piece so it's plenty strong and will most certainly hold a NES without a problem. However if you are afraid of it slipping just print it at like 102% scale and add some thin rubber between the mount and the console.

It is excellent at cleaning up my desk which is what it it supposed to, and it also looks kina nice too:)

I printed theese with a 0.25 mm layer height and 25 percent infill and no supports on my Creality Ender 3 and it ended up pretty great in my opinion.