Smoothing issue with static meshes from Blender - Rendering - Epic

I have been searching online for over a day and trying a heap of different settings and fixes to solve this issue, but unfortunately my lack of understanding/knowledge about smoothing/normals must be giving me trouble. There seems to be plenty of posts about similar issues but nothing seems to be a fix for me. I have made a high poly sculpt of a large rock, followed by a retopo into lower poly ready for UE4. I then export the low poly from blender as an FBX with the model set to smooth shading

Model ripping when smoothing and I don't know why : r/blenderhelp

Blender -> UE5 meshes become smooth : r/unrealengine

Shading issues with Blender made static meshes - Rendering - Epic

UE4 – Technical model visualization tips – Oded Maoz Erell's CG Log

Blender Add-on] Organize meshes with Volume Preserving Smoothing

render – Oded Maoz Erell's CG Log

Blender] Same model but different shading quality? - Asset

Too high resolution for this to smooth? - Ask - GameDev.tv

Problem with import smooth object from blender - Pipeline

How to export from Blender to Unreal Engine without the smoothing

Using Custom Controllers – Cesium