Arrange oven rack to be in the middle. Preheat oven to 350F. Grease baking sheet.
In a large bowl, cream together softened vegan butter and granulated sugar with an electric mixer on low speed. To the large bowl, add vanilla extract, flax egg, unsweetened applesauce, ground cinnamon, ground cardamom, baking soda, Kosher salt, gluten-free quick oats, and shredded zucchini. Mix everything together with an electric mixer on low speed.
Add 1:1 gluten-free flour and mix until combined with an electric mixer on low speed. Fold in 3/4-1 cup of blueberries.
Using a small cookie scoop (1.5 tablespoons), scoop dough out on the baking sheet leaving space in between. Using your fingers, press the cookies down a little bit to help them flatten while they bake.
Bake for 10-12 minutes, or until the edges are golden brown. Remove baking sheet from the oven, and allow cookies to cool for 3 minutes. Then transfer to a rack to finish cooling. Be careful when transferring the cookies. If you used a lot of blueberries, the cookie might not hold together as well when it's warm. It will firm up as it cools.