Hello,
You can rewrite etheme_sale_label_percentage_text() functon via functions.php of your child theme. https://developer.wordpress.org/themes/advanced-topics/child-themes/#using-functions-php https://webdesign.tutsplus.com/tutorials/a-guide-to-overriding-parent-theme-functions-in-your-child-theme–cms-22623 Please note that additional customization in files is out of our basic support scope.
Regards
