Preheat oven to 375 degrees F (190 degrees C). Grease 12 muffin cups or line with paper muffin liners.
Combine 2 cups flour, baking powder, baking soda, nutmeg, and 1/4 cup sugar in a large bowl. Beat 6 tablespoons butter, egg, yogurt, and vanilla extract in a bowl. Pour yogurt mixture into flour mixture and mix until just combined; fold in blueberries. Divide batter evenly among prepared muffin tins.
Whisk together 1/2 cup flour, 1/4 cup sugar, and almonds in a small bowl. Cut in 1/4 cup butter and almond extract with a knife or pastry blender until mixture resembles coarse crumbs; sprinkle over muffin batter.
Bake in preheated oven until golden and a toothpick inserted into the center of a muffin comes out clean, about 20 minutes. Let cool in muffin cups for 5 minutes before removing to a wire rack.