Size guide is just a popup with it’s content displayed for the variant/option we choose. You can insert popup and assign it to the variation to represent as the variation’s popup.
You can follow the below steps to insert size guide,
- Go to Product summary -> Add block
- Choose Information popup from the list of blocks
- Now you can add your option name at Variant choice to assign this popup.
To display the Size guide as per the block order, you can leave the Variant choice field empty.