ShipEngine Shipping will help your business to access deeply discounted rates across multiple carriers and display them in the cart and checkout pages, validate addresses before allowing place an order.
FedEx Shipping plugin for WooCommerce displays live shipping rates at cart / checkout pages and validates shipping address before allowing to place an order.
With that plugin you can calculate your shipping costs when you create orders in wp-admin.
Select a shipping method and the rate will be calculated for you.