My versions of the Pokemon trainers from all generations. I don't have all of their alternate designs, mostly just recent designs.
Red: The first trainer playable. He's based on a mix of his original Red and Green/Blue/Yellow appearance and his FireRed/LeafGreen/Smash Bros Brawl re-design.
Leaf: The girl playable in FireRed and LeafGreen.
Ethan (Gold): The Trainer from Gold and Silver, and Male trainer of Crystal, HeartGold, and SoulSilver. He's based on his HG/SS version.
Lyra: The female trainer of HG/SS and replacement of Kris from Crystal. She's obviously based on her only appearance.
Brendan: Male trainer of Generation III, he's based on his design from Pokemon Emerald.
May: Female trainer of Generation III, she's based off of her Ruby and Sapphire appearance.
Lucas: Male trainer of Gen IV, based on his Platinum design.
Dawn: Female trainer of Gen IV, based on her Diamond and Pearl design.
Touya (Japanese Name): Male trainer of Black and White.
Touko (Japanese Name): Female trainer of Black and White.
Black 2: Unnamed male trainer of Black and White 2.
White 2: Unnamed female trainer of Black and White 2.