Place chicken in a 3-qt. slow cooker. In a small bowl, whisk soy sauce, ketchup, honey, ginger and oil; stir in onion. Pour over chicken. Cook, covered, on low 3-4 hours or until chicken is tender. Remove chicken; shred with 2 forks and refrigerate until assembly., Meanwhile, in a small bowl, mix cornstarch and water until smooth; gradually stir into honey mixture. Cook, covered, on high until sauce is thickened, 20-30 minutes. Toss chicken with 3/4 cup sauce; reserve remaining sauce for serving., Fill a large shallow dish partway with water. Dip a rice paper wrapper into water just until pliable, about 45 seconds (do not soften completely); allow excess water to drip off., Place wrapper on a flat surface. Layer 1/4 cup coleslaw, 1/3 cup chicken mixture and 1 tablespoon noodles across bottom third of wrapper. Fold in both sides of wrapper; fold bottom over filling, then roll up tightly. Place on a serving plate, seam side down. Repeat with remaining ingredients. Serve with reserved sauce.