Entity references from a view with list of nodes that can be references to nodes that keeps references
Edit: this approach is only for listing the assignments, not changing them. 

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First make sure that the product content types have a common view mode. Pick "teaser" for example.

Create two views:


Products list: the "outer view" to list all the t-shirts, pants shoes.
Packages per product: based on a contextual filter, list all package assignments of a given product. As you have different fields link the product content types with the packages you might want to start with one type. Once it works, replicate the view/view display for the other product types.


The second view now needs to be embedded into the teaser view of products. My preferred way of doing so is using panelizer to override the teaser view mode but you can also do this using the "Eva" module.

Hope this helps :)