Magento – Add select quantity options on product page Magento 2

As per the updates in the original question, we found the below solution (workaround?) to provide the best way of achieving what we wanted. I think the only other way would have been to either create a completely new product type for these or implement some condition based extending of the configurable and grouped product types...

Further testing and the following scenario works:-

Retail Store

• Parent Product (00X) <-- This is a configurable
  • Child Product (00A)
  • Child Product (00A)
  • Child Product (00A)

Wholesale Store

• Parent Product (00Y) <-- This is a grouped
  • Child Product (00A)
  • Child Product (00A)
  • Child Product (00A)

The three child products under the configurable and the grouped are the same products. This means that only the parent product will have to be duplicated in the catalog (instead of every product).

• A parent product (configurable) for the retail store.
• A parent product (grouped) for the wholesale store.

The default add to wishlist link does this already by working with the quantity options used for add to cart. It will submit the add to cart from but update the url to be that of the wish list and not the add to cart.

productAddToCartForm.submitLight(this, this.href); return false;

But if you are not working on a page that has an add to cart form then simply supply the input field with name qty and the default controller will take it from here.

You can also simply add the value via the url it wanted:

/wishlist/index/add/product/554/form_key/QOTCSV8HqoLA0K3T/qty/7

This will add 7 of the product 554 to the user's wishlist.