Q: How I can do repricing on UK & US eBay marketplaces at the same time with File Exchange Sync Chrome Extension?
A: You can use 1 sku grid account to sell on both US and UK but it has to be for 1 eBay account that sells on both marketplaces. Regarding using the chrome extension, you would have to set them up and run them in 2 different google chrome profiles and never mix them up. Here's more information on setting that up. -->> Running the File Exchange Sync Chrome Extension for Multiple eBay Accounts, CLICK HERE
Another thing that you could do is purchase 2 remote chrome installations and set them up (1 for each eBay marketplace). The fee for that is $20/mo each but it will also allow you to run both without having to keep your computer on. Here's information on remote chrome as well. --->> Quick Start Guide to Using Remote Chrome, CLICK HERE