One thing you can try, which we have been using in 3D projects (as well as some internal UE tests) is using Vue to generate your cloud/sky environment, and then rendering that using a spherical camera for your latlong HDR.
One thing you can try, which we have been using in 3D projects (as well as some internal UE tests) is using Vue to generate your cloud/sky environment, and then rendering that using a spherical camera for your latlong HDR.