, such as moscato (optional)
CUT watermelon in half. Scoop out 20 balls of watermelon with melon baller. Stir balls with sugar in a medium bowl. Refrigerate until ready to use.
PEEL remaining watermelon and coarsely chop. You should have about 15 cups. Purée chopped watermelon with ⅓ cup mint and lemon juice in a blender until smooth. Strain purée through a fine-mesh sieve. The liquid that flows through should be clear. Do not push watermelon down. Discard pulp. Refrigerate until cold, about 2 hours. Stir in wine. Divide among 4 bowls. Divide blueberries among bowls and top each with 5 reserved watermelon balls. Sprinkle with remaining 2 tbsp mint.