I have imported a product dataset into Wordpress/WooComerce which has created the required categories and sub-categories correctly when viewed in the Product->Categories page.
When I go to try to create the menus from Product Category structure only a small amount of the subcategories are indenting. The first image show the indenting as it should be, the second image shows where it stops. It looks like it is not listing them in the correct order which may be throwing the sub-category structure which goes 3 levels deep.
There are just over 240 categories so I am not sure if this would cause an issue.
Is there any other way to import a large number of categories into a menu and maintain the structure.
wp_list_categories
(you'll need to use 'taxonomy' and set it to whatever name WC uses for Product Categories) in the theme. That way they're always up to date without anyone touching a Menu.