Yes, Stock Sync can display the differences between store and feed file values by enabling the preview sync option under the feed detail page.

To learn more about how the preview sync feature works, please follow the steps below:

1. Firstly, you need to set up the feed as per your requirements. Once the setup is complete, go to the feed detail page to initiate the process.

2. Before starting the process, ensure that you have selected the preview sync option. This will allow you to view the feed without making any updates.

3. By default, this option is disabled, so you must check it to enable it.

4. After running the process, check the comparison between the store and feed in the changes log. To access the log, click View More > Change Log.

5. When you no longer need to preview sync, simply uncheck it and rerun the process to update your stock or any fields.