Hi @alex.teepe,
While we have had developers successfully build OpenCV applications for the ML2 we do not currently have a public sample project with this implementation.
However, we do have a native fiducial marker tracking API, which you can find an example for in the Magic Leap Hub Package Manager.
Is it a hard requirement for you to use OpenCV, or are you just needing to use marker tracking in general?
We also support Vuforia Engine in Unity, which has a marker tracking library, as well as our own Unity guides and examples for marker tracking.
We suggest using one of the existing marker tracking methods if you want to get started quickly and don't have to use OpenCV.