Pokemon Glazed Trainer Rematch/XP Grinding

I want to rematch trainers in Glazed for quick xp, somewhat like the trainer right before Northcoast with the Pineco, Butterfree, and Kakuna. I know in BlazedGlazed there's one near the fire gym, any trainers like those in Glazed? The water gym in Seaspray is pretty hard rn and I need to grind levels, is there a better way than rematching trainers(if there are any)?