I understand the importance of importing employees' details in QuickBooks Online(QBO), normandy. I'm here to share insights about this.
Currently, the option to import employee details is unavailable in QBO. As a workaround, we can look for a third-party app that allows you to import data in QBO. You can find one by visiting this website: QuickBooks App Store.
I've added this article to learn more about importing data in QBO, here's a link that you may find helpful: Common questions about importing data to QuickBooks Online.
You're more than welcome to drop by here if you have more concerns regarding your imported data. I'm always here to help. Have a good one.