For anybody looking for similar in the future, the plugin mentioned above did the job very well.
I added a sortspec.md file to my vault’s content directory, and added the following frontmatter to it, then enabled the plugin.
The below also “pins” my inbox.md and todo.md notes to the top, and sortspec.md to the bottom. It then sorts in descending order, with most recently edited notes at the top.
sorting-spec: |
target-folder: content
inbox
todo
%
sortspec
order-desc: advanced modified