When listing your variation items on Etsy, Sellbrite combines the different variation fields into one custom variant per SKU.
For example, if your product includes the variation values Size and Color, we will create a custom variation for each size/color combination you have.
It looks like this:
When the variation dropdown is selected, you'll see an option for each combination:
Also, you'll see there is no inventory quantity for each variation, nor is there a price. Etsy does not allow us to send inventory quantities/prices/SKUs to variations, so all of the quantities will be available in the Quantity drop down, and the price will be whatever your default product price is.