Plugin qTranslate-X offers a way to maintain dynamic multilingual content on a WordPress site. While static localization is already excellently implemented and offered by WordPress framework through po/mo file framework, it is still impossible to maintain dynamic multilingual content without an additional specialized plugin, to a kind of which qTranslate-X belongs to. For example, what if you need to make title, content and excerpt of a page to be multilingual? In theory, it could be handled by po/mo files, but in an insanely inconvenient way.
To deal with dynamic content, qTranslate-X provides language switching buttons on applicable admin editing pages, which, once pressed, make all the text of multilingual fields to be filled with the language chosen. The instant language change happens locally in your browser without sending an additional request to the server, which makes it most convenient for bi-lingual or few-lingual sites, for example, owners of which perform the translation of content on their own. qTranslate-X does not provide a way to translate static strings, assuming that this part is already implemented and handled by the WordPress localization framework.
The plugin qTranslate-X is a descendant of qTranslate, originally developed by Qian Qin, while it undergone a significant changes in both underlying database framework and user interface. The design of page and post editors is drastically changed and improved to be much less vulnerable to WP updates. Instead of seeing multiple lines per each language for title, qTranslate-X provides Language Switching Buttons, which, once pressed, make all the text fields to be filled with the language chosen. The instant language change happens locally in your browser without sending an additional request to the server.
A general description, FAQ, and support forum are available at WordPress site https://wordpress.org/plugins/qtranslate-x/