If you list a Variational product on eBay and sold at least one Child Product, eBay will not let you change variations for the product. Once the Product is listed on eBay and has at least one sale, there is no possibility to change the inventory of Child Products, the name of Variations or options by which it varies (e.g. Color, Size), the number of Variations.
So, if you list a Variational product from Magento to the Channel via M2E Pro, eBay remembers its initial listed state on the Channel. In case you change/delete any Variation of the product in Magento, M2E Pro, or on eBay, the connection between the product is disrupted. Revise action cannot be applied to the product correctly and the error appears.
To avoid the error, change the Variational product back to its initial state. All options/variations should be the same as they were when the product was listed. Also, check options' titles. The quantity of the variations should be the same in Magento, M2E Pro, and on eBay.
If you need the new variational data to be displayed on eBay, you have to stop the Product and List under a new eBay Item ID.