I personally think that we are way off full genetic manipulation on living mammals. Genetic manipulation has been achieved on plants and is actually very useful (genetically modified plants to allow crops to grow in harsher conditions, yield more, etc.) however, I just don't see a benefit for genetically modifying living animals to make them become Pokémon. While it may possible, it seems to me that there would really be no beneficial aspects to it (apart from maybe making new style of pets for people) and it may even harm the animals in question which is unneeded cruelty for the sake our our entertainment, don't you think?
No doubt about it, I think it would be cool and it is certainly achievable - if not a long way off, But the drawbacks just seem to outweigh the benefits. Maybe another method that doesn't involve genetic modifying (I'm thinking holograms :D) would be more suitable.