Unity diff tool is a .net win form application developed using c# to find and display differences of two unity files in organised way.
Tool can be integrate in to perforce as custom diff tool for scene files also works for prefab, anim, material
Below video shows differences between two scene files GameRoom_Old (Old scene) and GameRoom (Latest scene)
Pink defines objects and properties are modified in latest scene.
Green defines objects and properties are added in latest scene.
Red defines objects and properties are removed in latest scene.