Sorry, but that’s a commercial plugin so I have no access to its code to provide a recommendation on how to proceed. As they have dedicated support services that should be available to you as one of their customers, you can ask their advice.
Information to include for them:
The Text Hover plugin functions by filtering text. By default, it filters ‘the_content’, ‘get_the_excerpt’, and ‘widget_text’. If the builder’s text box widget (or whatever component you are using) has its own custom filter, Text Hover could be made to handle that as well, with code like so:
/**
* Enable text hover for custom filter.
*
* @param array $filters Filters to handle for text hover.
* @return array
*/
function more_text_hovers( $filters ) {
$filters[] = 'custom_filter_name'; // Here you could put in the name of any filter you want
return $filters;
}
add_filter( 'c2c_text_hover_filters', 'more_text_hovers' );