Types of Teams
Hyper Offense typically has five or six offensive sweepers that share a common counter, with one Pokémon to set up Dual Screens (Light Screen, Reflect). Hyper Offense is typically fast-paced due to screens, and the fact that the Pokémon used typically invest in speed and attack/spA in order to outspeed and OHKO opponents quickly.
Stall is a slow playstyle, which makes use of Status Moves, PHazing and Entry Hazards. Generally in stall, opponents set up Entry Hazards and then PHaze the opponents with Whirlwind, Roar, etc, to accumulate damage. Adding to that, throughout the battle, the Pokémon use toxic to wear down the opponents, then protect themselves by using Protect. Most of the time the Pokémon in stall are defensive rather than offensive, and usually use Leftovers and recovery attacks to last longer than their opponents.
This playstyle involves using a few Pokémon to boost stats, then baton passing to a sweeper to increase its power, speed or defence. In Baton Pass, Espeon and Gorebyss are common due to Espeon's hidden ability allowing it to reflect Entry Hazards back to the opponent, allowing it to set-up quicker (and the fact that it's fast), and Gorebyss due to the fact that it can use Shell Smash with a White Herb and instantly power-up the sweeper it passes its boosts to.
Trick Room is a playstyle which involves using Pokémon with slow speeds, then using Trick Room to make them outspeed the opponents. Reuniclus is a common user of Trick Room, even outside of the TR play-style because of its high sPA power, and Magic Guard allowing it to OHKO and outspeed most opponents once TR is up. Trick Room is a hard play-style to play, however, due to faster opponents having access to Taunt – and without Trick Room up, it's a lot harder to beat the other play-styles on its own.