I have been experimenting with particles to create a cloud effect. Turned out pretty decent. I use a cubemap-like setup to fake volumetric textures by blendi
UDK Clouds with (fake) volumetric textures
Volumetric Clouds Unreal Engine 4.27 Documentation
FreetimeCoder
UE4: Step-by-Step to Creating Your First Volumetric Cloud Material
Working on Volumetric Clouds in UE4
Unity - Flowing Cloud Models? — polycount
UE4: Analysis of Volumetric Clouds and How to Use Them
CloudScape: Volumetric Cloud & Fog Library in Visual Effects - UE Marketplace
UltraScenery - Volumetric Clouds
Jordan Walker - UE5 Volumetric Clouds