I’ve noticed this is not a thing on the grammar dictionary here, and I think it probably should be, for those of us who want to move on to read classical literature in Japanese or understand the dialogue in a noh play. Maybe things like Western Old Japanese na plural marker (Vovin, Alexander [2020]. A Descriptive and Comparative Grammar of Western Old Japanese: Revised, Updated and Enlarged 2nd Edition, vol. 1, pp. 119–23)might be a bit too obscure an entry to add, but at the very least such basic features as ～ず, ～む, ～けり, ～そうろう, and some common kakari-musubi should probably be there.
