No reverse sort ordering that I know of.
You can use the (PIP) swap button to change between the last 2 sort selections.
You get the sort last chosen for the external hard drive.
(It sure would be nice to have a swap for that without going back to the internal list.)
Note folders are sorted by latest date in the folder as all have the same name but folders only apply to internal recordings.
I use DVR date and name sorts -- the only ones allowed for folders.
Changing the name of a recording forces initial capital and the rest lower case and truncates to 14(?) characters and upper/lower cases sort separately.
A word of caution, I have seen multiple external transfers aborted because I changed the internal sort order.
-Ken