Help for challenge championship

I want to get the Suzerain rank on the challenge championship, but the trainers there are incredibly difficult. I need a strong cohesive team of 3 to take down the championship and capture shadow Mewtwo. I’ve tried so many teams, but none of them worked because a) the pokemon weren’t allowed, or b) my strategy didn’t work out as expected. Any suggestions for team builds?

A almost flawless strategy formed by A_Wild_Noob_Appeared!
All credit goes to him, its just been explained by Nir and how to avoid some difficult trainers. You could get a set of these mons through the discord trade w/ 3 IV stones.
You’ll almost always win, I’ve gotten tons of IV stones from here.

OH MY GOD THIS IS BRILLIANT I knew entrainment was good but I never though durant could learn it along with having Truant. My god A_Wild_Noob_Appeared is a genius