Variations are multiple similar (but not identical) items in a single fixed-price (or Store Inventory Format) listing. For example, a single listing could contain multiple items of the same brand and model that vary by color and size (like "Blue, Large" and "Black, Medium"). Each variation can have its own quantity and price. For example, a listing could include 10 "Blue, Large" variations and 20 "Black, Medium" variations.
Type that uses MerchantDataVariationsType:
Call that uses MerchantDataVariationsType: