Leader of Jigglypuff Army
If they ever base a Pokémon region on Canada (as I suggested in another thread), they could make moose and loon Pokémon. We already have a beaver in Bibarel and a polar bear in Cubchoo and Beartic, so they could be non-native Pokémon who appear in said hypothetical region. Oshawott is a sea otter, who is found on the western coast of British Columbia, but he's a starter, so they'd probably have to create another otter Pokémon.
We need a crane. I’m still surprised after two decades we still don’t have a crane Pokémon which is really strange considering the bird’s importance to Japanese culture. They made one off of those Lucky Cat store statues but not for their national bird? Also surprised we don’t have a Pokémon based on toxic metals.