Entitled collectively as From the Journals of Queen Jurai Achi, I have only three entries so far, though potentially more could arise if needed.
The first is a prophetic vision, of an ancient war reborn. Not so secretly, this segment outlines major events to come, and I pulled heavily from an old study of the Book of Revelation in my college years to pen the imagery.
The second is of the origins of the keys, a different vision from the OVA. This segment features the knights, Azaka and Kamidake, and their matron goddess, Tsunami. The imagery here was also very religious, harkening more toward Genesis or Exodus.
The third is the Legend of the Two Knights, heavily based on Ayeka's exposition in Universe episode 22. This segment has less abstract imagery than the first two but was intended to connect back to Universe and how the story was passed through the ages to Ayeka.
Naturally, these segments are in continuity with my previous works: vMiB, Reunion, Inheritance, and Homecomings. However, since these journal entries would predate all of these stories, knowledge of the larger works is unnecessary. However, I watch of Tenchi Universe wouldn't hurt.
EDIT: I actually had dropped a link to this story before, but the original post was more toward another story idea rather than the Journals story itself.