Display a collection as variants on the edit product

[teshan]

I am using ReCharge subscription app on my shopify store. In there I have a collection with a number of products in it. Rather than adding product options to the existing products I want to display a collection of products as variants/product options with images when I choose to swap/edit product. Is there any possibility to do this? Currently I have seen in this community to show variants as products but not the other way around. 

[teshan]

The basic requirement is to get products listed in Shopify to be shown as variants in  Edit Product sidebar popup in ReCharge subscriptions app.

Plus I wish to know how the coding should go for this in the ReCharge subscription theme (in "_edit_subscriptions.js") or the place where I should work on.