Many times, when you have a multilingual website in Joomla, the only reason why you have to duplicate every YOOtheme Template... is that you want to manually translate a few words (like a title or a sentence).
Flart Studio is about to release a new tool allowing to simply type a shortcode which will then use the native system of Joomla, based on Language Strings.
https://flart.studio/
Example :
{fslang="JYES"}