If this appeals to you, here’s where you can get the Narcissus Electric Egg Yolk Mixer.
I’m not sure what the point is of doing this. According to the video, the egg with the yolk and white completely mixed tastes pretty much like regular egg white. The manufacturer seems to agree, noting as one of the gadget’s advantages:
Egg yolk is very nutritious, but its mouth taste is not liked by many children and adults. With Narcissus egg yolk mixers, you can mix egg whites and yolks before cooking. That will make egg yolks easy to be accepted and eat [sic] by children.