Spiky-Eared Pichu is a lighter shade of yellow. A normal Pichu is a little darker. It obviously has three spikes on her ear, hence its name. The Spiky-Eared can only be female.
The Spiky-Eared Pichu cannot be shiny since it just joins your team and can't actually be caught.
No, the Spiky-Eared Pichu can't be traded over by WIFI. You can transfer it from SS/HH to black/white(2) with the relocator. Contact a scientist in castelia city to unlock this.
The Spiky-Eared Pichu can't be bred even though it's always female. Not even with a Pichu, Pikachu, Raichu or a Ditto. Anytime you want to bread it the day-care man will tell you:" Your Pokemon prefers to play with other Pokemon then with eachother. Well the Spiky-Eared Pichu is quite old since it lived in the time of Damon XP.
Strangly, it can't. It will never evolve so don't even start training it. You could if you want to, but it will never evolve
Hope this helped.
The arms and the right ear
Yes but it is preset to not be shiny
No
It is set to not evolve
Source