Okay, but that's still too out there. Living in a polluted region wouldn't do that to a Pokemon. (I know it was for a different project, though. For what it's worth, your concept sounds fun I wouldn't like it in Reborn, but that's a Pokemon hack i'd play.)
Here, I whipped up some sprites.
See, the basic Pokemon are a little bit different; I altered small markings and added the affects of pollution to them. However, as they evolve you get to see how they have overcome this- the damage has been done, but this doesn't stop the Pokemon from moving on. Shiny Bibarel and Swoobat look stronger for the experiences they've went through.
Is it worth doing? I don't know. But pollution and completely redesigning a Pokemon are two different things. Zombie Machops have no place in Pokemon- especially not a project such as this. Reborn aims to add a sense of realism to the Pokemon world, not craziness...