Preheat oven to 325°F and line a 9x13-inch baking dish with parchment paper. Set aside.

In a large saucepan, combine 2 cups of blueberries, sugar, and brown sugar. Cook over medium-high heat until sugar dissolves and blueberries start to burst.

In a small bowl, whisk together cornstarch and water until smooth. Pour into blueberries and stir until mixture thickens. Remove from heat and fold in remaining 1.5 cups blueberries and lemon zest. Cool slightly.

To prepare crust, toast pecans in a skillet over medium heat until browned and fragrant, about 3-5 minutes. Let cool. In a bowl, combine melted butter, flour, and toasted pecans. Press into the bottom of the prepared dish. Bake for 15 minutes and cool.

In a mixing bowl, beat heavy cream until thickened. Gradually add confectioners' sugar and beat until peaks form. In another bowl, beat cream cheese until smooth. Gently fold whipped cream into cream cheese and spread over cooled crust.

Top the cream layer with the cooled blueberry mixture. Chill in refrigerator for at least 1 hour before serving.