Cutlass.
UVs:
channel 1 - non-overlapping
channel 2 - non-overlapping (for lightmaps baking)
Textures:
For UE4 and Unity engines. (PBR).
Have proper naming according Epic Games asset naming rules.
Resolution: 2048 x 2048 px (TGA).
Albedo, Normal, Roughness, Metalness, Ambient Occlusion.
Unreal Engine 4 optimized RGB mask which includes R, M, AO.