Preheat oven to 350°F.
In a medium bowl, stir together the graham cracker crumbs, sea salt, sugar, and cinnamon. Drizzle with the melted butter and frangelico and stir until well combined. Press the mixture evenly onto the bottom and up the sides of a 9-inch glass pie plate. Bake 10 minutes. Transfer to a wire rack to cool completely. Leave the oven on.
Make the key lime filling
In a bowl put 2 T agar, 2 T cold water and whip with mixer, place in fridge.
Place cashews, lime juice, zest, and salt in blender and blend until cashews are creamy. Add in the sweetened condensed coconut milk and blend until fully mixed. Do the same for the agar.
Gently spread the mixture in the pre-baked crust and bake 10 minutes. Transfer to a wire rack to cool overnight.
While cooling make the whipped cream. Cut the pie in 8 pieces, serve on a plate, garnish with the whipped cream, a key lime wedge, and some key lime zest.