"装卸货计数人" can be translated as "person responsible for counting during loading and unloading" or more concisely as "loading/unloading counter" in a context where the role is clearly defined (e.g., in a warehouse or logistics setting).
The choice depends on the specific context and level of formality:
"Person responsible for counting during loading and unloading" is more descriptive and ensures clarity.
"Loading/unloading counter" is concise but assumes prior understanding of the role.
For example:
"The person responsible for counting during loading and unloading must record all items accurately."
"The loading/unloading counter will verify the shipment manifest."
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