Shortcut Expert does not have a user login system. It saves user favorites to the browser memory. Therefore, favorites can not be synced between different browsers and devices.
However, you can download your favorites as a JSON file, and upload it to another browser / device. When you upload it to another browser / device, the existing shortcuts in the memory will be merged with the uploaded favorites. So, if you want a clean start, do not forget to clear the memory before the upload.