Build in a highball. Fill with ice. Add equal parts vodka, passionfruit syrup, and cranberry juice over . Mix well. Fill with ginger ale. Stir lightly. Garnish with a couple small basil leaves.
Might work well with some muddled basil. For Passionfruit syrup, make 18 oz 1:1 simple syrup. Add 1 cup thawed frozen Passionfruit pulp (Maracuya in Hispanic markets) and 1/2 tsp citric acid. Bottle by the fifth with 2 oz vodka for stability.
Finally found a good source off passionfruit pulp. This is the second thing I thought to do with it.