This "plugin" does not contain any code.
It only provides a safe place in WordPress where NH3 Mag users can manage translation of custom content, such as categories names.
The NH3 Mag WordPress theme uses the categories names (as defined in the category section of the WordPress site) as a translation key, in order to display those names in several languages.
Since categories can be added an deleted by the admin users at any time, their names can not be added to the .pot model file of the theme, which is generated from the source code.
Using Loco Translate, those admin users can add the names of the created categories in the theme model and, thus, translate theme in the different languages.
But this workflow has an issue: those added categories names are not part of the source code of the theme. This means that, whenever some changes or updates are made to the NH3 theme, the .pot model file will be generated anew from the content of the source code, effectively removing all those user added categories names.
Separating translatable string of the source code (in the theme) from translatable user generated string (in this plugin) prevents this issue.
The plugin is only composed of a single folder, languages, that contains in itself only one file, nh3-mag-translated-custom-content.pot, which is an empty model file ; and some PHP files, that sets up the plugin and load the translations.
Admin users can manage their custom content translations by using the Loco Translate WordPress Plugin, through its Loco Translate > Plugins menu entry, and then select the NH3 Mag - Translated Custom Content link.