Into each of 8 (6-ounce) Champagne flutes, add 1/4 cup chilled cranberry-pomegranate juice and 1-1/2 tablespoons chilled coconut vodka; gently stir. Top with 2 cans (12 ounces each) chilled lime hard seltzer; garnish with 8 pieces candied ginger and fresh cranberries, if desired.