Face ID didn't allow you to create multiple users. This has changed with iOS 12, because this version now offers at least the possibility to add a second person for Face ID.
Follow our step-by-step instructions to use this convenient feature on iPhone X, XS, XS Max and XR:
How to add a second person to Face ID
1. Open your iPhone's iOS settings.
2. Scroll down to "Face ID & Code".
3. Tap on "Set up an alternative display".
4. Let the person you want to add as a second user do the steps for the Face ID Scan. If it was successfully added, you will see a green checkmark.
You have now successfully added a second person. This person can now also unlock your iPhone X, XS, XS Max and XR via Face ID.
