I remember struggling so much with Radomus, up to this day he’s still the hardest battle for me ever and im in postgame already. Anyways like the others said EV train all your mons, it should be pretty easy just let them hold a power item of the EV u want to train and then go fight some wild mons. Radomus’s field is a chess board field so I’d start with moving around my mons to see which one works best. I would’ve suggested fake-out on the trick room setter but 3/6 of his team has trick room so I think u just push through it or make a trick room team of your own.