There may be cases where you want to paint a mesh and then share those vertex colors with other instances of the mesh in the same level. For example, if you had a pillar mesh you were using in an outdoor map and you wanted to paint the base of the pillar green, and have all instances in that map only appear that way.
Instanced vertex color data can be copied and pasted between instances in the level very easily using the Copy and Paste buttons in the Mesh Paint Dialog.
To Copy Instanced Color Data:
Select the instance that contains the color data to be copied and press the Copy button.
Select the instance(s) to copy the color data to and press the Paste button.
The color data should now be applied to all of the instances.