Build custom "variation product bulk upload" functionality by coding in woocommerce -- 2

I have a clothing ecommerce website. I have thousands of products uploaded in the amazon. I want to import all the products in bulk by building a plugin/ functionality in my eCommerce site automatically. You have to create custom fields for my unique variation products. My 1 single product has 16 variations on average. One design of my cloth has multiple sizes and 4 colors variation for each size which concludes to almost 16 variations per product. I also need to have unique sku per product and unique price per product I have tried almost all bulk upload plugin, but there is no plugin with such that depth of bulk product upload functionality. Whoever reading this should know that finding, researching and installing any plugin will not work. You have to code in the backend of the woocommerce and my site to build this functionality. So if you are just a normal drag and drop Wordpress developer then please don't waste your time because this project will not help to earn you even single buck