Matrixify

It would be a great tool to use to support large data for my store. But unfortunately, they do not sign ADA's being supplied by major Suppliers.

As a drop shipper who are partnered with major Suppliers who are required ADA agreements to protect themselves and their brands from outside exposure is essential to avoid competitors, and exposure to data. This is not the right platform for you.

You must have a great understanding of excel to use this app. It makes it seem like you can do all of this easily. The person on the video is going so fast it's impossible to keep up.. You CAN NOT merge individual products into one matrix

It would be nice to know that Matrixify does not download or convert customers' or order files to Shopify before pre-paying the subscription.
The support channel is also not helpful. They only direct you to pages instructing product migrations; the rest you figured out!