Unlit Clouds

Is there a way I can make clouds similar to this video (Ue4: advanced materials (Ep. 39 Making Simple Dynamic Clouds) - YouTube) using unlit materials?

The method at the video relies on a mesh with material using displacement to get a form of cloud… the stilized shape looks good, but you will get low performance if you want several clouds:

-> each one is a mesh (better effects need some amount of vertices to match the tesselation)
-> the tesselation itself if spread over your scene will impact performance aswell

My asset Cloudscape Seasons uses unlit material and I use raymarch sampling a subuv texture (each subimage contains a slice from the noise mapped in 3D) created with perlin noise + voronoi, interpolating between each slices, to fill the density between the slices. I do in the same material the shading according to the main directional light and the anisotropic effect (rim light) aswel. Color and turbulence effects are giving by other means. You need to check my videos: UE4 - Cloudscape Seasons - Demo small - YouTube