A Loadmaster in the military does both. When the acft is carrying cargo, they create a load plan, coordinate ground movement and distribution, load and balance the aircraft, fly to the next destination, and offload, then start over again for the next load of outbound cargo. When Passengers are carried, in addition to everything else, they board, brief, and monitor the safety of all PAX on board. Loadmasters are also in charge of military airdrop procedures, in-flight jettison of cargo in an emergency, and act as a liaison for the Flight Engineers (if used) and pilots for the status of the cargo and passengers. They also work with aerial port personnel to develop long-term and large-scale continuing cargo and passenger movement plans throughout the bases of operation. They are also responsible for classifying and safety of hazardous cargo, reg mail, and signature service deliveries. Before every flight, they also prepare a loadsheet and briefing for the Pilots. It's basically a Load Controller, Baggage / Cargo Handler, Ground handler, and Dispatcher all rolled into one.
"Never trust a clean Crew Chief"