I only require to use FedEx Packaging but the packages listed in the Plugin does not include PAK XL, which is Height 44.4 cm, Width 52.7 cm and 2.5 kg. It offers the same price as the regular PAK, instead of using boxes and increasing the cost on my customers. I tried adding it but it calculated as using one of my packages and increases the price.
Unfortunately FedEx API has only the FedEx Pak option.
I have attached the screenshot of the packaging options in FedEx in the link here : https://ibb.co/h7e4wF