I’m wondering if it’s possible to achieve an effect like this bloom, but in UE4: brigade3 on Vimeo
If you look at the specular highlights, they bloom out into a starburst effect instead of a soft bloom like UE4 does by default. Sprites wouldn’t solve this because they can only be placed at emissive light sources like car headlights, and I think you’d need to do some pretty crazy math if you wanted them to appear on specular reflections.
I noticed in the documentation on subsurface profile shading that a similar effect is achieved unintentionally: https://docs.unrealengine.com/latest/images/Engine/Rendering/Materials/LightingModels/SubSurfaceProfile/Bad_Combination.png
I assume this “bloom” wouldn’t extend off the object in this case, so it would be fairly useless, but maybe it will give someone an idea.