Place fresh blueberries in the freezer until ready to use. Preheat the oven to 350 degrees and line a large baking sheet with parchment paper. In a large mixing bowl, combine flour, baking soda, baking powder, and salt with a whisk and set aside.
With an electric handheld mixer or in the bowl of a stand mixer fitted with the paddle attachment, combine room temperature butter, brown sugar, and granulated sugar in a separate bowl.
Mix on medium speed for about four minutes until the mixture is light and fluffy.
Add eggs, vanilla extract, and lemon zest and continue mixing on medium-low speed until combined, scraping down the sides of the bowl as needed.
Add flour mixture and continue mix on low speed until fully incorporated.
Add the old-fashioned oats and fold with a spatula to combine.
Add the fresh blueberries that have been chilling in the freezer and again fold with a spatula to combine.
Using a one and a half tablespoon cookie scoop, form the dough into balls and place on the parchment-lined cookie sheet at least one and a half inches apart.
Bake for 12-14 minutes until edges are set and turn golden brown. Remove from the oven and allow to cool on the baking sheet for at least ten minutes.
Transfer the blueberry oatmeal cookies with a spatula to a wire baking rack to cool completely. To store, transfer to an airtight container and refrigerate for up to four days.