Create a new project. (HoloLensWithOpenCVForUnityExample)
Change the platform to UWP in the "Build Settings" window.
Import the OpenCVForUnity.
Setup the OpenCVForUnity. (Tools > OpenCV for Unity > Set Plugin Import Settings)
Move the "OpenCVForUnity/StreamingAssets/haarcascade_frontalface_alt.xml" and "OpenCVForUnity/StreamingAssets/lbpcascade_frontalface.xml" to the "Assets/StreamingAssets/" folder.
Clone HoloLensCameraStream repository.
Copy the "HoloLensCameraStream/HoloLensVideoCaptureExample/Assets/CamStream/" folder to the "Assets/" folder.
Set the scripting backend of the plugin inspector to "Any Script Backend". (IL2CPP support)
Import the Microsoft.MixedReality.Toolkit.Unity.Foundation.2.2.0.unitypackage.