Here is a step by step guide to help you translate the WP Rich Snippets plugin using the CodeStyling Localization Plugin that can be downloaded from WordPress.org website.
1- Install the CodeStyling Localization Plugin
The CodeStyling Localization is a free plugin that can be download it from here (you also can install it directly within your WordPress dashboard), start with downloading/installing the plugin on your WordPress website, then head to the Localization page under the Tools menu.
2- Add New Language
Click on the Add New Language button as showing below:
3- Choose Language
A window will pop up, choose your Language from the list, and click on the Create po-file button as shown below:
4- Click on the Edit button
Now, click on the Edit button.
5- Start translating to your own Language.
A new page will open and you will see all wording that you can translate to your own Language.
6- Translate & Save
Now it’s all about translating every word and save the translation.
7 – Generate mo-file
Once you are done with the translating , click on the generate mo-file button and make sure you select Textdomain: “wprs”.
8- Check via FTP
Make sure that you’ve got two files in the languages folder that is located at:
9- Check your wp-config.php file
Make sure you are have this line in your wp-config.php file with the exact Language of the file name, example:
define ('WPLANG', 'ar_EG');
If you have a different name set on that line above, then make sure to edit the files name to match it.
10- Backup the translation files
It’s highly recommended that you make backup of the .po and .mo files and save them in a safe place on your computer, so when you upgrade the plugin you can always upload these two files again to the Languages folder. (Let us know if you have created translations so we can add it to the plugin core files).
You are done!