$ for f in ***/*(/l2); do foo=($f/*(N)); [[ -z $foo ]] && print $f; done
# Note:Since Zsh 4.2.1 the glob qualifier F indicates a non-empty directory.
# Hence *(F) indicates all subdirectories with entries, *(/^F) means all
# subdirectories with no entries.
$ ls -ld *(/^F)
$ for f in ***/*(/l2); do foo=($f/*(N)); [[ -z $foo ]] && print $f; done
# Note:Since Zsh 4.2.1 the glob qualifier F indicates a non-empty directory.
# Hence *(F) indicates all subdirectories with entries, *(/^F) means all
# subdirectories with no entries.
$ ls -ld *(/^F)