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I'm not an expert in Unreal. For the difference between Pawn Actor and Character, what scenarios they should be used for, etc., I suggest you seek support from Unreal. For the Project Settings used when creating HoloLens Unreal project, please refer to Creating your first HoloLens Unreal application - Mixed Reality | Microsoft Learn. We should use C++, Scalable 3D or 2D, Mobile/Tablet.
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