There's this thing most companies have called an "Asset Library".
GF should have YEARS of assets and animations built up.
Ding ding ding. Unfortunately, I don't know that Gamefreak can do anything about the animations at this point. There are just too many Poke'mon to animate for. So we will likely never get nice, detailed battle animations. They would have to remove a bunch of Poke'mon first to make it more manageable.
see above ^^