Supporters - These are very big in VGC, as they allow other Pokemon to deal more damage, move quicker, and take hits. The series 5 meta was dominated bun Togekiss, a very supportive offensive supporter, that used Follow Me to protect allies from attacks, letting them set up or just live hits. Other support Pokemon include Dusclops, who sets up trick room, allowing slower Pokemon to move quickly and Whimsicott, who uses a prankster Tailwind to boost ally’s speed and Taunt to block other supporters, and the ultimate support Pokemon was in Incineroar. With access to Fake Out and Partibg Shot as well as a good attack stat, it’s pretty amazing.
Sweepers - These also have VGC usage. Physical sweepers include Rillaboom, a huge offensive Pokemon that has terrain control and Fake Out and Exadrill, who is amazing in sand teams because of Sand Rush. Special sweepers include Togekiss, who is also used as a sweeper as well as supporter, making it very versatile and Venusaur, who also had Sleep Powder as well as great sp. attack.
These are the main Pokemon used in VGC, but there are other roles like tank, which Celesteela used highly in 2017 and 2019.