I want to make day/night transition like in UE4
Is there any solution?
We don’t have that particular feature.
I’m thinking you might be write something custom using an inverted sphere and a shader to transition between textures/colours.
See how skybox is implemented in the engine here:
you could use similar code, and implement what @yaustar suggested.
I suppose you could also enable alpha blending, and lerp the ‘Intensity’ of the material down to zero.