You can copy UV, shader, and color per vertex attributes between faces of different polygon meshes using the Mesh > Clipboard Actions features. The ability to copy UV attributes between meshes is useful when a polygon mesh has been modified and you cannot further modify the UVs. It is also useful for copying attributes between meshes that have differing topologies.
You can only copy attributes between polygon faces that have similar vertex counts. The copied UV attributes are placed in a separate shell.
To copy UVs, shaders, or color per vertex data between polygons
The previously copied attributes are pasted onto the selected face.