Size Guide

First - go to WPBakery Page Builder > Role Manager and under the user roles, choose the post type is Custom and check the post type you want to use the WPBakery Page Builder (nasa_block)
Simply go to Static Blocks > Edit Size Guide
Please navigate to Appearance Theme Options WooCommerce Extended to know the position we have designed the Size Guide:

In addition, you can override Size Guide for Root Category Product (Parent=0)