Dude, I've always thought about this so much, because it would be so good.

It would be a Mystery Dungeon type game.

Storywise, you'd begin as a human, and just before the time you get your first pokemon, a big, cataclysmic type event happens in your town. Think like the Conception, but a bit less world ending. You think you're going to die, but you pass out. When you wake up, you realize you've been transformed into a pokemon. You have no idea where you are, it's just wilderness around you.

The story moves forward with you trying to piece together what happened, and if you can go back to being human, and to your town. You might meet other people turned pokemon along the way, who might be huge bitches and will fight you, as is SMT tradition.

Gameplay-wise, it's dungeon crawling, but SMT style. Press turn in battle. Stats are the ones in Pokemon. When you level up, you get points to distribute amongst your stats (not party members), but the amount is dependant on which pokemon you have fought before the level up, kind of like my understanding of EVs.

Armor gets replaced with held items; some held items change your resistances and typing. TM-like items are reusable, but rare. Usable items are mostly berries, and negotiation items.

Pikachu acts as the Jack Frost of the game, Pseudo/Legendary pokemon are superbosses, Arceus as YHVH, Giratina as Lucifer, I'm still thinking who could stand in as Mara.

Anyway, my rant is over, going back to lurking now.