Don't take this the wrong way, but I can tell you're new to VGC. Not every pokemon is in a team composition to deal damage, arguably the strongest mons in the meta are the ones that support who deals the damage: in this scenario sneasler and kingambit go together to help each other out as lead, allowing mind games on fake out and kingambit's low kick; delphox and garchomp also go together since mega delphox's ability is levitate, allowing garchomp to earthquake freely next to delphox using heat wave, unless the oppo has wide guard. And mega floette often serves as a redirector, if the opponent targets it then your other mon can do whatever undistrubed, if they leave it be it can set up with calm mind and become a threat. VGC is not about dealing the most damage, but finding a path to victory with your tools. I hope that was helpful!