Products sorted by Category.DisplayOrder then ProductCategory.DisplayOrder (this caters for products associated to multiple categories, where the order might be different in each one)
Actual behaviour:
Products sorted by ProductCategory.DisplayOrder from first/random category
Steps to reproduce the problem:
Set catalogsettings.showproductsfromsubcategories to true
Create two products
ID, Name
1, ProductA
2, ProductB
Associate products to the categories
CategoryID, ProductID, DisplayOrder
2,1,1
2,2,1
3,1,2
3,2,1
The products should be ordered by the Category.DisplayOrder then the ProductCategory.DisplayOrder, instead they are ordered by the DisplayOrder of the first ProductCategory (which in practice is similar to sorting by CategoryID then the Products DisplayOrder in the first category it is in)
nopCommerce version: 4.60.2 (and later versions)
Source: https://www.nopcommerce.com/en/boards/topic/98936/searchproductsasync-ordering-ignores-category-order-in-default-sort