Thanks for your post. Currently, the inventory would need to be managed manually and uploaded via CSV file. Go to their Seller Center - Click on the Manage Items tab on the left, then click the Download icon - select Download catalog, a dialog box will pop up allowing you to download your Item Report, which contains detailed information about your entire catalog
ShippingEasy can update stock numbers based on received, committed and shipped inventory. However, your store's inventory levels will be unaffected by inventory integration.
One-way syncing/updating is supported when orders contain SKUs. Most store platforms allow merchants to add SKUs to their product lists, although you may need to update your store's settings to make use of this function.