Phrase

This plugin allows you to send page or post content to your Phrase projects, directly from within WordPress. Once translations are done, send them back to WordPress and easily publish multilingual sites.

Phrase Strings

Phrase WordPress Integration. Phrase is a translation management platform for software projects. You can collaborate on language file translation with …

OzTheGreat

Adds a multiple select box to every non-admin user profile that allows admins to 
select which languages that user can see / edit in the wp-admin.
Languages that a user cannot see are hidden. If they try to switch surreptitiously 
it will throw an error message.
This plugin REQUIRES WPML and is useless without it.

WPML Editor Languages

Allows admins to restrict users to specific languages in the WordPress admin

Phrase Strings vs WPML Editor Languages