The error message "Total commodities weight is greater than package or shipment weight" concerns FedEx international shipments when the total commodities weight synced from EC store is greater than the package weight input in Ship&co.
Ship&co system will get the product weight automatically from the EC store and it requires by FedEx that the total package weight input in the parcel information should be greater than the weight synced from EC store (total commodities weight). In the case that the you input the wrong weight inside EC store and revise product information after the order is paid, please be noted that the change will not be synced to the order with paid status.
Therefore, to avoid this error, we suggest you to create order manually inside Ship&co application with the same order information and print the label.
After the label is printed, you will have to fulfil order manually (marked as shipped & input the tracking number).
Find more information about how to create a new individual order manually from here.