Sign up for an account at inkFrog https://www.inkfrog.com/
Sign in to your eBay Account
Select the I agree button to allow eBay to share your eBay data with inkFrog.
Once you’re returned to inkFrog, you will see your eBay ID added to the account.
Once you’re within your new inkFrog account, navigate to Apps → Channel Connector, click the Add channel button and choose Amazon.
Enter your Amazon seller display name and select the region, then click continue
Sign into Amazon Seller Central
Follow the prompts to add Amazon to your inkFrog account
Once you’re returned to inkFrog, your Amazon account connection is complete. Next, select Sync & inventory control to manage how your Amazon products sync with eBay.