Oh a little demo of what we can do with a command line support:
$ wp polylang language info fr
Code: fr
Locale fr_FR
Name: Français
RTL: no
Installed: yes
$ wp polylang get post 1 en
1
$ wp polylang get post 1 fr
7
$ wp polylang languages
fr — Français [DEFAULT]
en — English
$ wp polylang language add nl
Success: language added.
$ wp polylang languages
fr — Français [DEFAULT]
en — English
nl — Nederlands
$ wp polylang language del xx
Error: xx isn't a valid language code.
$ wp polylang language del eo
Warning: This language isn't installed.
$ wp polylang home nl
http://wordpresslanguagestack.threyscend.drake/nl