Pour enough oil into small saucepan to come 1/4 inch up sides of pan. Heat oil over medium-low heat. Using tongs and working with 1 wonton at a time, submerge wontons into hot oil, frying until golden brown, about 15 seconds for first side and 10 seconds for second side. Transfer fried wontons to paper towels to drain (wontons will continue to color slightly as they cool). Sprinkle fried wontons with cinnamon. Cool completely.
Place 4 fried wontons on work surface. Spread 1 tablespoon of whipped topping over each. Arrange 1 sliced strawberry and 2 to 3 raspberries over whipped topping on each wonton. Spoon 1 tablespoon of whipped topping over berries on each wonton. Top with another fried wonton. Repeat layering 2 more times. Spoon dollops of remaining whipped topping atop each cake stack. Garnish napoleons with remaining strawberries and raspberries, and mint sprigs (optional). Serve immediately.