Preheat the oven to 350℉.
Heat a large nonstick pan with high sides over medium heat. Add the butter and the sliced apples to the pan and cook for 5-10 minutes.
Transfer the apples to a large bowl and add the sugar, cinnamon, nutmeg, clove, strawberries, and cornstarch to the apples. Gently mix until everything is coated in the sugar and spices.
Transfer the apples and strawberries to the store-bought crust.
To make the crumble topping, add the crumble ingredients to a bowl. Using a fork, cut the butter into the oats and flour. Top the pie with the crumble topping.
Bake for 25 minutes. Remove from the oven and cover the crust with tin foil. Place back in the oven and bake for another 20 minutes.
Remove from the oven and allow to cool on the countertop for 1 hour to thicken. You can also store in the fridge overnight and serve the next day.