Preheat oven to 350 degrees F (175 degrees C). Line a baking sheet with parchment paper.
Combine ground turkey, chicken sausage, bread crumbs, basil, milk, garlic, Parmesan cheese, kosher salt, and black pepper in a bowl; mix gently with a fork. Drop mixture, about 1 1/4-inch diameter per meatball, onto the prepared baking sheet using a spoon.
Bake in the preheated oven until cooked through and lightly browned, about 30 minutes. An instant-read thermometer inserted into the center should read at least 165 degrees F (74 degrees C).