To disconnect eBay Sync, please follow these steps:
1. On the left side WordPress menu, go to eBay Sync > Settings > Store Admin
2. Scroll to the bottom of the page
3. Tick the 'Reset and delete all created listings' box to end all your eBay Listings
4. Click the 'Reset eBay Sync' box to disconnect the plugin and de-authorise access to your eBay account.
5. Go to your eBay Seller Hub and check that all listings have ended.
6. Go to WordPress > Plugins > Installed Plugins
7. Scroll to eBay Sync and click on 'deactivate.' Once that's done, click on 'delete.' this will remove the plugin from your WordPress site.