For the Buffalo Glaze combine the melted butter, hot sauce and lemon juice. Season to taste with salt and pepper.
Preheat grill to medium.
Place the pickerel on a flat surface and season with bbq seasoning, pressing the spices gently into the fish. Brush lightly with olive oil. Set aside.
Mix together the red onion, yellow pepper, crabmeat, parmesan cheese, green onions and dill. Season to taste with salt and pepper.
Spray grill topper with non-stick cooking spray and place on grill
Place pickerel/walleye skin side down on topper and grill for 3 to 4 minutes. Carefully turn over and top with crab Parmesan mixture and continue to cook, drizzling with buffalo glaze until fish is cooked just through, about another 3 to 4 minutes and the topping is hot.
Serve with steamed mussels