How to Achieve sunbeam effect without changing visual?

I want to achieve godray effect called (sunbeams)

So i did searching and i found this video. https://www.youtube.com/watch?v=Akb4P71KL0s
his using unreal engine and to achieve that effect, he used volumetric fog and result was amazing.

And various researching, I was tested two way to achieve that effect.

first way is using volumetric object and placing light

The result was great however, the scene was very foggy. Physically this correct but, i don`t want my scene looks foggy. so i decided to not using this method.

Second way is compositing.

In blender, there`s sunbeams node. And i achieved the effect what i want!
however my scene is animation. i have to manually change the sunbeam position using keyfream.
this method looks so tedious and result will be looks weird (I think.)

I really want to get that effect without any changing visual in my scene. is that possible?

Using a tut for a game engine to do it in blender… Why not just search for blender sunbeams ??

for example…? Because:

  1. fog … can be adjusted…
    1.a. or rendered seperatly
  2. 2D compositon… of course not while real 3D camera movement but there is 1.a and…
    2.a. 3D composition with seperate fog layer (1.a).