Question Access GameObjects created by AR Face Manager

I am using AR Foundation to build an application that has a world-facing AR Camera and a AR Face Manager. The idea is to use facial features tracking to animate a cartoon face and display it in the physical environment, like the example given here (https://developer.apple.com/documen...mbining_user_face-tracking_and_world_tracking). I added the AR Face component to my face prefab and assigned the prefab to the corresponding field in AR Face Manager, and this facial tracking part worked fine.

However, I am not sure about how to access the GameObject created by AR Face Manager, namely the animated cartoon face, such that it can be placed at arbitrary physical positions at runtime. I have not found any up-to-date documentation regarding how to implement this feature and would appreciate your help.