Can a non-high school graduate transfer to a four-year college without a high school diploma or GED?

Unless you have a book deal or other famous work that could give you leverage for acceptance, it is not likely. The minimum colleges ask for is high school completion. You could likely attend community college and gain more course work there, but the fact remains that when applying to a four-year university, transcripts are always requested.

Most jobs also require you to have a high school diploma at the bare minimum, so if you plan on working anywhere, you will need to finish high school.