When a project is created the default list of work types will be copied to its Estimated Work & Rates section. After removing any unnecessary work types and adding any custom ones, this list becomes the pool of work types that will be available to anyone adding time to that project.
However, there is not a way to assign one of these work types to an individual person. Each person on the team will have to select the work type that best applies to the work they were performing.
That said, there is a creative workaround you can employ to approximate this functionality. One method is to name your work types so that they are role based. For example, your list of work types might include “Graphic designer,” “System administrator,” or “Senior Developer.” Naming your work types in this manner makes it much easier for each person to select their work type. You could also include the person’s name in each work type and make it even more obvious which one to select. For example, a work type could be named “Analyst – John.”