Judging by the image and the description of the Five-Man Band:
Greninja: The Leader (The leader of the group. Can be a mastermind, charismatic, levelheaded, headstrong, or some combination of the four. Often also The Hero.)
Lucario: The Lancer (Usually a contrast to The Leader. If the Leader is clean-cut and/or uptight, the Lancer is a grizzled Anti-Hero or Deadpan Snarker; if the Leader is driven and somewhat amoral, the Lancer is more relaxed and level-headed.)
Pikachu: The Smart Guy (The physically weak, but intelligent or clever member. Often nerdy and awkwardly played for comic relief. Sometimes unconventionally young (early- to mid-teens). Sometimes a Trickster and a buddy of the Big Guy.)
Charizard: The Big Guy (The strongman of the team. May be dumb. Or mute.)
Jigglypuff: The Chick (A peacekeeping role to balance out the other members' aggression, bringing them to a nice or at least manageable medium. The Chick is often considered the heart of the group. This role is played by a woman or girl. Someone female. Otherwise, it is not a Five-Man Band.)