Any owner of successful affiliate website can tell you that best conversion and commission are in local popular shops. There are many good plugins for affiliate marketing, but all of them are working with big networks, because local shops don’t have own API and don’t take a part in any affiliate networks. This is why we created Affiliate Egg plugin, which are working with many shops which don’t work in any other plugin.
Demo: https://codecanyon.net/item/affiliate-egg-niche-affiliate-marketing-wordpress-plugin/21852757