If we're talking in terms of strength then Satoshi's SM team was by far the strongest out of the main cast, with Kaki's team and Suiren's team coming in at second and third place, respectively. I just can't decide on who I think is stronger among the other classmates, although Maamane might have more technical battling skill than Mao and Lilie I suppose.
I think Lillie could match up to Sophocles strategically, just she didn't really bulk up Snowy (she might stand a chance with Magearna though). Sophocles had similar brain power but still some token amount of strength by evolving Vikavolt and training it some hard hitting attacks. Mallow was the opposite of Lillie, having a fully evolved Pokemon and a mythical but not really any idea of how to use them resourcefully, she was stumped in a match she couldn't win through spamming.