How can I order all files and directories by last access date?

Solution 1:

Open a new finder window with CMD+n. If it doesn't default to "Recents" - choose it. Hit the cog, and choose "Show Search Criteria".

This takes you to a "Raw query" (other views will also do the same - I just use this as it's not grouped), choose to view by "list";

This enables the column headings, which you can now use to affect the sorting order. Just click on "Date Last Opened" until it sorts by oldest first;

And ... that's it! Obviously, it won't care about files you've never opened but that's fine. TBH, I use CleanMyMac for this type of thing, as it builds an index so you can sort by various attributes (e.g. file size is a good one) very easily.