Make the sage simple syrup: In a small saucepan over medium heat, combine the sugar, water, and sage leaves. Bring to a simmer and cook, stirring frequently, for 3-5 minutes, until the sugar is dissolved. Remove the pot from the heat and let cool for about 10 minutes.
Add the ice to a cocktail shaker. Pour in the pomegranate juice, mezcal, simple syrup, and lime juice. Shake well.
Add the dry ice to a lowball glass and pour the cocktail over the top.
Garnish with a cinnamon stick and fresh sage leaf.