Landed Cost Allocation / Custom Duty manual data entry

Landed Cost Allocation / Custom Duty manual data entry

My client is an import business. They must manually enter the duty for each item with landed cost allocation in Bill. This is because customs duties cannot be allocated based on Quantity, Value, Weight, and Dimensions.

Manual data entry is highly time-consuming as they frequently import more than 100 items at once. 

Does someone have the same issue? And if you have any solution, please share it with me.