I installed and checked the plugin, unfortunately, it seems that there is no option on the product page to select pre-made size charts, and it seems that the only way to insert the size chart is to use its short code.
The yith size chart plugin has such a possibility and the possibility that I said in the first message (general shortcode). If this plugin has such a possibility, it will be great and it will be a great alternative to the YITH plugin, and of course, the great advantage of this plugin is that it is free