this is Rivals of Pokémon Yellow Gamma Yγ
A rival (Japanese: ライバル rival) is one of the main characters in the Pokémon games that is well known to the protagonist and has similar skills, goals, and achievements. Rival characters appear frequently during the hero's quest, having a role in several of the games' events and often challenges him or her in battles. Defeating a rival may be a primary or necessary goal of said character.
Sometime during the three years between the Generation I games' plotline and the events of the Generation II games and their remakes, Pokémon HeartGold and SoulSilver, Blue took the place of Giovanni as the Viridian City Gym Leader, as Giovanni had mysteriously disappeared after he disbanded Team Rocket. Blue does not specialize in a particular type of Pokémon and, like Giovanni before him, he gives anyone who defeats him an Earth Badge.
Red (Japanese: レッド Red) is the canon name of the player character in the Generation I games Pokémon Red, Green, Blue, and Yellow and the male choice in their Generation III remakes Pokémon FireRed and LeafGreen, where his female counterpart is Leaf.
Leaf (Japanese: リーフ Leaf) is the female player character in Pokémon FireRed and LeafGreen. In her debut, Leaf is presumably 11 years old, the same age as her male counterpart, Red. She lives in Pallet Town, next door to her upcoming rival in Pokémon training, Blue.
the character which is not selected by the player will alter-ego and the second rival of the player
Silver (Japanese: シルバー Silver) is the rival character of Pokémon Gold, Silver, and Crystal and Pokémon HeartGold and SoulSilver, playing opposite Ethan, Kris, or Lyra. He is the son of Team Rocket Boss Giovanni.
in the game Silver called Kamon (Japanese:カモン Kamon) inspired to the pokemon hack DarkViolet it is very mysteriousBut He tells you that stalking the Team Rocket Organisation (it often appears at the same time as Team Rocket)