Some more general ideas about Pokémon Trainer:
N Special: PokéBall, Trainer throws a PokéBall to capture an enemy, can be charged to throw stronger capture ball, starting with PokéBall (every 10th PokéBall will be a Premier Ball, color change only) then a Great Ball and finally an Ultra Ball. It captures the enemy, similar to Yoshi's Egg Lay, while captures, PokéBall can be picked up and thrown, and used like a Pokémon-less PokéBall. Button mashing can allow enemy to break the PokéBall faster.
U Special: HM Fly, by raising his arm into the air, a PokéBall Flash summons the generic bird Pokémon that carries Trainer into the air strongly, works similar to Snake's U Special. If U Special is pressed again, Trainer commands his bird Pokémon to use Aerial Ace nearby, punishing opponents coming in for an attack, although doing so causes Trainer to be dropped by his Pokémon. Does not leave Pokémon Trainer helpless after use, but he cannot use U Special or air dodge.
S Special: HM Cut, Very quick and powerful attack, short range but swipes in front of opponent with a quick slash, silhouette looks like a blacked out Scyther. Sweet spot on very edge of the slash, doing extra damage. Can be used to safely cut away projectiles, but does not reflect them.
D Special: HM Whirlpool, Trainer summons the overworld sprite of a Surfing Pokémon underneath of him, which then spins, causing a vortex of water with a strong vacuum effect, drawing enemies in, although can be punished from above. Can be held for longer use. When used in the air, it causes Trainer to slow his decent, allowing him to better control his fall speed.
Dash Attack: HM Surf, Pokémon Trainer slides on top of his Surf sprite Pokémon quickly. Weak attack, but leaves behind a trail of water, that has tripping properties, can be useful for punishing dodgers, as they can slip on the puddles of water left behind.
Special: HM Rock Climb, when Pokémon Trainer is trapped underneath or next to the stage and it not close enough to grab the ledge, when he pressed A he can latch onto the side and quickly crawls up the wall a short distance. The area in which Trainer moves is short, but can allow for recovery. If Pokémon Trainer fails to hit a ledge or recover before the distance has expired, he is in helpless state.
F Throw: Throw Rock, Trainer knocks enemy forward and lobs a rock at them, causing them to fall to the ground as a trip, however there is a 1/10 chance that Trainer will Throw Bait instead, meaning he throws a Riceball item.
B Throw: Repel, Trainer tosses opponent behind himself and pulls out a Repel, spraying it in their face and repeling them away.
(Or maybe Repel can be Trainer's N Air?)
D Throw: TM Dig, Slams opponent to the floor with a PokéBall release animation, before the ground explodes and knocks opponent into the air, possible silhouette of Dugtrio. Best move for possible KO.
U Throw: TM Teleport, Trainer spins with opponent help before it teleports opponent into the air, leaving Trainer on the ground.
Final Smash: Bill's PC, Pokémon Trainer becomes invulnerable as he summons several of his stored Pokémon out of PC, he quickly starts lobbing PokéBalls out, player can control only if they are thrown forward, back, or upwards using the directional pad. Randomly uses 6 PokéBall items consecutively.
