we use fedex to do shipping for our goods. how come the shipping cost does not show up on the item fulfillment GL impact

Item Fulfillment GL impact only shows the inventory. Shipping is tied to the Sales Order/Invoice/Cash Sale.

shipping cost will show on the invoice, cash sale.

its on our cash sales but with the sales order shipping cost rate not the actual rate we get that's on the item fulfillment

are you using shipping cost (standard netsuite field) on item fulfillments or is your actual cost in a custom field on IF?