Preheat oven to 350 F. Grease 2 loaf pans. Mash bananas and combine with sugar, orange zest/extract, orange juice, vanilla extract, butter, and egg. Stir thoroughly. Combine dry ingredients in a separate bowl and mix well. Sprinkle blueberries with 2 TBSP of dry mixture and stir until coated. Add wet to dry ingredients and mix gently until combined. Fold in blueberries and walnuts. Pour (batter is thick) into loaf pans and bake 40-45 minutes until centers are done. Cool 10 minutes before removing from pan to a wire rack to cool.