AutoBlend is a Blender add-on from specoolar that blends objects in screen-space using the Compositor and Cryptomatte. It runs as a post-processing effect, which keeps it independent from scene complexity and materials. You can blend any number of objects and any type of material apart from transparent ones, and there is no need to modify meshes or materials — you only choose which materials to blend.
The add-on works with both EEVEE and Cycles, though Cycles carries some limitations: realtime preview, depth of field and motion blur are not supported directly, and depth of field can be recreated with the compositor's defocus node and motion blur with the vector blur node. For more organic results, you can use Noise, Voronoi or custom masks, with auto setup available for the Noise and Voronoi masks.
As a screen-space effect, AutoBlend can show artifacts such as fading when another object blocks the view or flickering when the blending distance is too large, so a smaller distance is recommended. The effect cannot be exported to game engines or baked, and blending between instances of the same object is not supported. It requires Blender 4.5 or newer and is compatible up to Blender 5.0.