A retro console in today's market isn't going to sell. I've said it before and I'll say it again, my opinion of course!
but in all seriousness, you can buy any old, true "retro" console for around $40-$80 and they have a huge library of games you can get fairly cheap.
A system like the Retron 5 that can play games from a half-dozen systems and has a halfway high price survives because it can play thousands upon thousands of already released games and has tricks up it's sleeve like running translation files. It also has ports for your original controllers.
This thing is a flop from the word go.