One way cruise to Hawaii and a return say a week later on another cruise ship?
As a general matter, I’m not aware of any maritime law provision that prohibits purchasing a one-way passage from one port to another on one vessel and then purchasing another one-way passage on a different vessel for a return trip. That is as a general matter. However, a person’s rights, duties, and choices for a given passage(s) can also be determined by specific terms and conditions provided in a particular ticket, travel package, contract, or other arrangement entered into with a vessel operator, travel agent, or other travel-related entity.