Occasionally I need to find the most recently downloaded file in my Downloads directory but may not know the exact file name. Here is how I do it.
ls -rt ~/Downloads
ls -t lists the files by time not name, with the most recent being displayed first. Since my Downloads directory contains so many files I don't want to scroll to the top of the list to see the most recent.
ls -rt reverses the order of the list, displaying the most recent file at the bottom of the list.
From there you can do what you need quite easily. For example:
unzip $(ls -rt ~/Downloads | tail -n1)
mv $(ls -rt ~/Downloads | tail -n1) *some_other_location*
Your original question could be done like this:
7z l $(ls -rt ~/Downloads | tail -n1)
I realize this is not adhering to the Tab completion method but it may be suitable for your needs.