Place potatoes and water in a 2-quart microwavable dish. Microwave, covered, on HIGH 8 minutes or until potatoes are tender, stirring halfway through cooking.
Place potatoes, shrimp, sausage, corn and onion in large bowl. Add butter and Seasoning Blend; toss to coat. Divide mixture evenly and arrange in center of each sheet of aluminum foil. Bring up sides of foil; double fold top and ends to tightly seal packet.
Grill over medium-high heat 10 minutes or until corn is tender and shrimp are cooked through. Garnish with lemon wedges before serving, if desired.