Possible Pokemon
>Ethan/Gold
Meganium, Feraligatr, Typhlosion, Togekiss/Togetic, Red Gyarados, Hitmontop, Sudowoodo, Espeon or Umbreon, possibly Snorlax or Shuckle too.
>Brendan
Sceptile, Swampert, Blaziken, Wobbuffet, Castform, Kecleon, Metagross
>Lucas
Torterra, Infernape, Empoleon, Glaceon or Leafeon, Drifblim, Blissey, Lucario, Porygon Z, Togekiss, possibly Rotom
>Hilbert
Serperior, Samurott, Emboar, one of the Simis, Musharna, Darmanitan (Zen), Zoroark, Volcarona, possibly Zekrom or Reshiram