sounds fantastic if you can keep the walleye from flaking apart! I would say make a seafood base (or can buy seafood stock at some stores), add whatever veggies you want.. spice it up how you like it, add the shrimp and boil until cooked. Add the walleye in chunks, turn it off and let it sit for a few minutes. It isnt going to take but about 5 minutes to poach the fish. Then serve immediately over rice or in a bowl.
That is how I would make it, but like any soup/stew… the possibilities are endless.