Given the fact that the context in which these terms are coming in is “import & export”, and seeing that we have two acts of “transportation”, I think that the first “نقل” is about “freight or shipping”* whether it may be “sea or air freight “. Now, the terms in question “ حمالة ونقالة “would accordingly mean loading/discharge “حمالة” and “transportation” for “نقالة”.
One way to for easy understanding of how and why the said terms are meant in the template at hand is to consider one of the shipping terminology and its definition, i.e. “demurrage:
What is demurrage?
Demurrage is a result of a failure to abide by the rules agreed to in a charter agreement. Specifically, it is when a charge is payable to the owner of a chartered ship on the failure to load or discharge the ship within an agreed time period.
When a ship is chartered, there is usually an allotted time for delivery to be taken and for receipt by the warehouse. This time specified is usually no longer than 3 days.
To understand who is responsible for delay; a penalty is assessed against a consignor, consignee, or other party who is deemed to be responsible for any delay in loading or unloading a shipping vessel. Delays may also stem from any undue detention (usually over 48 hours) of the transportation equipment. This is also called a detention charge.

* The usage of two terms here rather than one is to account for an import vs export activity, since that in the latter case “loading” is the appropriate term, whereas the “discharge” applies for the former, i.e. import.