In this short tutorial I’ll show you how to merge three grayscale textures into one RGB channel packed texture.
https://dev.epicgames.com/community/learning/tutorials/zzb/textures-channel-packing-layers-in-photoshop
Thank you so much for this!!
I recently started modding textures for a UE game with barely any help so far, so this has been a huge and helpful eye-opener!