Can I create an order for only a shipping charge?

There is no way to create an order for just the cost of shipping. Orders in Commerce7 require at least one SKU in the cart before you can set a Shipping Rate.

If you need to add a shipping charge to an order, we would recommend performing a refund on the original order (without shipping) and re-processing a new order with shipping added.

For more documentation on refunding an order, click here.