Chouby

WordPress, your theme and your plugins are all written in US English. The possibility to use them in your own language is one of the greatest features offered by the community of translators. Unfortunately, this comes at a high price. The translation process slows down your site. A lot. At least by 20% for a fresh install and generally much more for a site using a few plugins.
DynaMo uses a different way to handle the translations which increases the performance compared to the method used by WordPress. How much it will improve your site performance will depend on your install. But the more (translated) plugins, the more difference you will observe. In our own tests with a few popular plugins (WooCommerce, Jetpack, Yoast SEO and Elementor) we measured a page generation time decreased by 25%!
If you have object cache activated, DynaMo will automatically switch to another method to take profit of it for even more benefit.
Install and activate the plugin as usual from the ‘Plugins’ menu in WordPress. That’s all. There are no settings.

DynaMo

Improves the performance of WordPress translation

Louy Alakkad

This plugin gives you the ability to run the site in a language (Arabic for example) and use the admin panel in another (like English).
Just go to Settings » General and choose your language.

Admin Locale

This plugin allows you to change the language of the admin panel without changing the whole site language.

DynaMo vs Admin Locale