There is no one job that is most in-demand in freelancing, as the needs of clients vary depending on their industry and project. However, some skills that are always in demand include writing, editing, web development, graphic design, and marketing. If you have any of these skills, you should be able to find freelance work relatively easily.
That said, it’s always a good idea to stay up-to-date on the latest trends in your field so that you can be sure you’re offering services that clients are actually looking for. Keeping your portfolio updated with your latest work is also a good way to show clients what you’re capable of and make them more likely to hire you for future projects.