Coconut oil is pure fat vs vegan butter being a combination of fat, water and flavoring with often some salt too. You can probably switch the coconut oil for vegan butter, although start with a little less water first and add some more as you go. Also, if using a salted vegan butter, then omit the salt in the recipe. Although more processed, vegan butter will give you a crust that's a little more flaky with added flavor too.