Can I use FedEx only for international orders and handle Shopify domestic shipping separately?

Yes, this is a common setup. You can configure your Shopify shipping settings to handle domestic rates, such as flat rates or another carrier, separately, while reserving FedEx specifically for international shipments. Domestic orders simply won't use the FedEx rate calculation in that case.

If you want a reliable way to keep these two shipping flows organized without conflicts, PH Ship, Rate & Track for FedEx can be scoped to specific shipping zones, letting you dedicate FedEx to international orders while Shopify handles domestic rates independently.