>>109672507See
>>109672703It's just one of those little artist fads/memes that go through fandoms; it starts off fun, and eventually the artists get bored or people start getting annoying about it.
Honestly, I think it's a lot of fun visually, since it asks you to pick and choose the parts of each character design, and then mix them together. Sometimes, it looks pretty lame, but with the right characters, you can find some oddly appealing esthetics.