EDIT: This is entirely a documentation problem. The feature I want already exists, as order:change and order:change_asc. This needs to bed documented here: https://e621.net/help/cheatsheet
Requested feature overview description.
Users would be able to write "order:updated" to sort posts such that the posts that were most recently updated are displayed first, and "order:updated_asc" for the inverse.
Why would it be useful?
For a newly created tag, I would like to verify that the posts are being tagged correctly. If I was able to sort by recently updated posts, I could view which posts have been most recently tagged and verify they are correct. Also, this feature would be useful for tagging projects, where the posts most recently updated are less likely to need tagging overhauls.
What part(s) of the site page(s) are affected?
Searching and sorting.
Updated