Preheat oven to 325°F. Line 12-cup muffin tin with paper liners.
Mix graham cracker crumbs, melted butter, 2 tablespoons sugar, and salt. Press 1 tablespoon into each liner. Bake 5 minutes, cool.
Beat cream cheese with 2/3 cup sugar until smooth, about 2 minutes. Add vanilla, lemon zest, and sour cream. Mix until combined.
Add eggs one at a time, mixing just until incorporated. Fold in flour gently.
Divide filling among crusts, filling 3/4 full. Bake 18-22 minutes until edges set but centers jiggle slightly.
Cool completely in pan, then refrigerate at least 2 hours.
For topping, cook blueberries, 1/4 cup sugar, and lemon juice over medium heat 5-7 minutes until berries burst. Stir in cornstarch slurry, cook 1-2 minutes until thickened. Cool completely.
Spoon cooled blueberry topping over chilled cheesecakes. Serve cold.