Can an actor work as their own agent, sending resumes and pictures and be successful, or is it better to have an agent?
Unfortunately, every facet of Japanese society is regulated by Hakken Gaishas (middle man companies). I really don’t think you would do well, because it is going against the system. Japanese are very particular about following the system no matter how stupid we or they think it is. You are better off just registering with the agencies and accepting jobs from the ones that pay well, and pay promptly. The agencies are covered for insurance, etc, so from a Client’s perspective it makes a lot of sense to use an agent.