My guess (I stress the word 'guess') is that it might be possible to ship a moto from South Korea to Anchorage, but it's less likely that you could ship one in the other direction.

Anchorage is a hub for freight, but the freight containers (ULDs, or 'Uniform Load Devices') that hold the freight often don't get broken down in Anchorage - they just get transferred from the incoming Korea flight onto other widebodies that will take them further into North America. Or, if the containers do get broken down, it's at an in-house operation where the incoming contents get spread out amongst a number of other aircraft operate by the same carrier (e.g. UPS or FedEx or Polar) to go to various destinations served by that carrier. In other words, it's not like Anchorage is a 'post office' where individual pieces of shipments get sorted or pulled out of the stream.

The only way to achieve really inexpensive air shipment of motorcycles is to identify routes where wide-body passenger aircraft fly with excess cubic volume on the lower deck, but not excess weight capacity overall. An example of this is Air Canada's summer motorcycle shipping program.

On a busy air freight route like Korea - Alaska, the aircraft are likely both cubed out and near max weight. This means that if you want to ship something that has high cube but low weight (a motorcycle), you will end up paying for 'cubic weight', which will make the shipment very expensive.

All things considered, my guess is that it would probably be less expensive to buy a moto in South Korea and sell it there when you are done, or investigate renting a moto in South Korea.

If you want to investigate the air freight option further, I suggest that you call air freight consolidators in Korea, not the air carriers. The air carriers think in 'pallet loads' (ULDs), not in individual boxes or crates.

Michael