Preheat oven to 350°F. Unroll piecrusts on a lightly floured work surface. Using a 5-inch round cutter, cut piecrusts into 12 circles, rerolling scraps as needed. Reserve remaining dough scraps. Press 1 circle in bottom and up sides of each cup of a lightly greased (with cooking spray) 12-cup muffin pan, flattening any bunches of dough along sides. Fold over top edge; pinch to seal. Press tines of a fork at an angle to create a design in crust edge. Freeze 30 minutes. 

Meanwhile, gather remaining dough scraps; roll to ¼-inch thickness on a clean work surface. Using 1 ½-inch leaf-shaped cookie cutters, cut dough into 24 leaves. Using the back of a small knife, make lines resembling veins on leaves. Place in 1 layer on a parchment paper-lined baking sheet; brush lightly with egg. Bake in preheated oven until golden brown, 10 to 14 minutes. Cool completely on a wire rack, 20 minutes. 

Meanwhile, combine pears, cranberries, granulated sugar, salt, nutmeg, 4 tablespoons each of the flour and light brown sugar, and 1 teaspoon of the cinnamon in a bowl; toss to coat. Let stand 10 minutes.

Combine oats, butter, and remaining 2 tablespoons flour, 1 ½ tablespoons light brown sugar, and ¼ teaspoon cinnamon in a bowl. Use fingers to rub butter into mixture until it is crumbly and butter is incorporated. Remove pan from freezer; fill each piecrust with pear mixture (about ⅓ cup each). Sprinkle with oat mixture (about ¾ teaspoon each). 

Bake at 350°F until tops are golden and filling is bubbly, 26 to 32 minutes. Remove from oven; cool in pan 15 minutes. Using a small knife or offset spatula, loosen pies. Transfer to a wire rack, and cool 30 minutes. Decorate with piecrust leaves. Serve warm with ice cream, or cool completely, about 1 hour.