1. Choose one of the listed trainers

2.Battle in OU

Took me a while but here they are the trainers:

Ash [Kalos League]: Ash-Greninja, Talonflame, Pikachu, Hawlucha, Noivern, and Goodra

Ash [Indigo League vs Drake]: Pikachu. Squirtle, Tuaros, Lapras, Bulbasaur, Charizard

Ash [Diamond/Pearl]: Pikachu, Staraptor, Torterra, Infernape, Buizel, Gliscor

Alain: Mega Charizard X, Metagross, Tyranitar, Bisharp, Weavile, Unfezant

Cameron: Lucario, Ferrothorn, Samurott, Wathog, Swanna, Hydreigon

Giovanni: Persian, Golem, Rhydon, Kringler, Machamp, Cloyster

Blue: Nidoqueen, Magmar, Blastoise, Golem, Scizor, and Arcanine

Paul: Electrive, Agrron, Ninjask, Gastrodon, Drapion, Frolass

Barry: Empoleon, Staraptor, Roserade, Heracross, Skarmory, Hitmonlee

Gary: Nidoqueen, Magmar, Blastiose, Arcanine, Scizor, Golem

Drake: Ditto, Onix, Venasuar, Gengar, Electabuzz, Dragonite

Red: Kabuto, Jolteon. Hitmonlee, Victrebell, Snorlax, Charizard

Tyson: Meowth, Metagross, Sceptile, Shiftry, Donphan, Hariyama

Katie: Golduck, Venomoth, Dugtrio, Misdrevious, Scizor, Walrein

Nando: Kricketune, Loppuny, Altaria, Armaldo, Sunflora, Roserade

Conway: Shuckle, Aggron, Slowking, Heracross, Lickilicky, Dusknoir

Sawyer: Sceptile, Salamance, Slurpuff, Aegilsash, Clawitzer, Slaking