Muddle lime wedges and sugar in the bottom of a shaker to release juice.
Add mint leaves and press gently.
Add rum, pineapple juice, coconut water or cream, and ice. Shake well.
Strain into a tall glass filled with ice. Top with club soda.
Garnish with pineapple slice and mint sprig. Serve immediately.
Notes
For a lighter mojito, use coconut water; for a dessert-like drink, use coconut cream. Add more syrup for sweetness, or chill the glass for extra refreshment.