So, short version:
- Trainers are mostly FAE-like. Approaches are swapped by Conditions (in the Pokémon sense): Cool (straightforwardness), Tough (resistance to change), Beauty (interpersonal relationships and carefulness), Smart (using your mind to do stuff), and Cute (deceiving others to get what you want).
- Build trainers just like you would build a FAE character, with Conditions instead of Approaches.
- Have no stats on their own. They're as good as their trainer.
- At least two aspects: Species + Nature (i.e. Adamant Bulbasaur), and Types (Grass/Poison). One more aspect is allowed for in-depth background. I even used the latter to justify Egg Moves.
- Moves are literally a laundry list of things each 'mon can do. They have no special effects on their own. Agree on the usage of each with the players, and make them spend stunts if the move requires it. Build each 'mon with whatever moves you want, grab a learnset and pick your favorites. Use Fate's actions to emulate the effects accordingly. The only requirement is to use physical moves with Cool and special moves with Beauty. Tough and Smart are your fallback defend Conditions, and Cute is your fallback for Status moves. Judge accordingly with each move. And, buy stunts if you think the moves need better effects.
- Moves are learned at each minor milestone, whenever you can swap your Conditions. Swap at most one move with one other move that Pokémon can learn.
- Abilities are just glorified stunts that can only change upon evolution.
- An EXP stress track exists. Check a box when certain conditions are met. When you cannot check a box, you go up one stage, clear the boxes, and earn a new box. At certain stages, your Pokémon can evolve if able, which changes the species aspect. A Pokémon with a superior stage swaps 1dF with 1d6 in their rolls for each stage that Pokémon is better than the opposition.
Those I think are the most important bits.