How do I combine monthly sales data from 4 sales channels that structure data differently?

This is my approach but I'm getting stuck. I now there is a better way but I can't seem to find it.

1. I create four folders, each for the different sales channel
2. I then create four different excel files, each with a Power Query that goes into each corresponding folder and transforms the data to be exactly the same as the other sales channels.
3. Once having 4 excel files with the data structured identically, I create a fifth excel where I copy paste and dump the data of the 4 excels

This solution involves a loooot of manual work and I was wondering if there is any other more smooth process that would work by me just updating the sales folders every month.