The leftover honey syrup is divine drizzled over oatmeal. (Remove sage¸ cover syrup and refrigerate for up to 1 month.)
Bring honey and water to a simmer in a small saucepan over medium-high heat. Remove pan from heat and let cool completely, about 10 minutes.
Muddle sage leaves, 5 tablespoons of the pomegranate seeds and 2 tablespoons of the honey syrup in a cocktail shaker to release flavors. Add gin, pomegranate juice, elderflower liqueur and enough crushed ice to fill shaker halfway. Cover with lid and shake vigorously until thoroughly chilled, about 30 seconds.
Strain into 2 collins glasses filled with crushed ice. Top each glass with ¼ cup of the club soda; sprinkle with remaining 1 tablespoon pomegranate seeds.