martinjuhasz

Lets you choose your Backend Language for your complete Backend, also if your Frontend is using another Language (including Multisite). 
You can choose from any language you installed. For a list of availible languages, check <a href="https://codex.wordpress.org/WordPress_in_Your_Language" rel="nofollow ugc">“WordPress_in_Your_Language”</a> or create your own files.

One Backend Language

Lets you choose your Backend Language for your complete Backend, also if your Frontend is using another Lang (including Multisite)

mendezki

Using an English WordPress install and publishing posts in Dutch? Those pesky English dates produced by <code><?php the_time(); ?></code> and <code><?php the_date(); ?></code> were getting on my nerves too, hence this plugin. Automatically converts english months and days (except for the initials, so far) to their dutch equivalent.

DutchDate

Replaces english day and month names with their dutch equivalent

One Backend Language vs DutchDate