I’ve just published another collection of essays from the Patreon on Amazon: Myths from Fudoki Fragments 2. (Affiliate link!) This book includes three essays on Shinto-related myths found in fragments of the eighth-century Fudoki, texts compiled by Imperial order to describe the regions of Japan. Not all of the fragments are genuine, but it is impossible to be sure which are real, which are later paraphrases, and which are entirely spurious. This is something I discuss in the book.
This collection includes the original version of the Urashima Tarō story. While my commentary does mention, and indeed translate, the (very condensed) version in the Nihonshoki, it does not mention the version in the Man’yōshū, because I wrote these essays before I read the Man’yōshū and discovered that version. The notes to the Fudoki do not mention the poem, and the notes to the poem do not mention the Fudoki. What do these people think notes are for? The essay covering the Man’yōshū version is available on Gumroad, and will be on Amazon in a few months.
The book covers a lot of other myths as well, some of which are very fragmentary and probably not genuine, some of which are just baffling (there is a poem attributed to Okinagatarashihimë that is, shall we say, hard to interpret), and some of which sound like versions of myths that are attached to other locations. There are also some interesting new myths, so if you are interested in the diversity of the early tales we have from Japan, please take a look.