Decalmachine

DECALmachine is a blender addon, which through mesh Decals, allows for surface detailing in a very non-committal, non-destructive, UV-less way. As such it represents an alternative approach to hard surface texturing.
In addition DECALmachine has deep Trim Sheet support, and supports Atlasing, as well as Baking to facilitate exporting to game engines like Unity, Unreal Engine etc.

It is the most advanced, most complete, and most flexible decal-workflow solution in the 3D industry.

Decals can be projected, sliced, created from grease pencil or edges. They can be material matched, and you can easily create your own.