Radial Blur PostProcess Material

Im having troubles making this work on mobile ES2.
Some comment in this thread from 2015 says ES2 does not SceneTextures while the documentations states PostProcessInput0 is supported. (see screenshot + link)
Rendering Features for Mobile Games in Unreal Engine | Unreal Engine 5.2 Documentation -> just CTRL+F “PostProcessInput0” or look below

Any idea how what the problem could be?

If have tried only using the PostProcessInput0 and multipling it by some float4 to give it a tint and that did work.
I assume the problem is the “SceneTextureLookup()”, I could be wrong.
Mobile HDR is enabled and other Post Processing effects (like DoF) work on mobile.

Thanks!