Site Language

Hi all,

Is there anyway to dynamically change site language?

My client does not want to implement a WP multi-site because of safe certificates costs and neither allows me to use translation plugins like Polylang. I could solve most issues through CSS and scripts but a few are still unsolved (eg. search field prompts, social icon tooltips, footer copyright notice).

Though I have a body classes (myLangEn, myLangSp, myLangFr, …) that define the page language, I could not figure out or find any script to change de global WP language setting dynamically.

All suggestions appreciated.
Darío.

The page I need help with: [log in to see the link]