How is the following anti-aliasing technique called if it even exists and how effective is it?

Question

I've seen a couple takes on aa-techniques and I wanted to see what types of AA there are. I got an idea on an anti aliasing technique but when looking at the existing ones I didn't see anyone doing my idea. The idea is the following make a buffer triple the size of the frame buffer where you keep the what I assume would be called triangle id. after all previous stages run as normal raster at triple the resolution keeping only the triangle ID information (I don't know if you need to keep the object id too I just would want to be able to differentiate a triangle from another). After the frame buffer is complete but before post process you sample the color from the frame buffer with the following directives:

• Consider each pixel from the framebuffer is a 3x3 grid in this new buffer.
• The center position will always copy directly the information of the frame buffer.
• the bordering positions of the grid compare if the triangleID of this position is the same as the center triangleID.
• if it is copies the information of the frame buffer of this position.
• if it isn't it copies the information in the direction of the offset from the center.
• after this you downsample/average the framebuffer by the amounts.

Description of the image

• On the left the original buffer colored to keep track of which pixel is which.
• On the right from where we would sample each pixel to then create the average.

Does this exist? Would this look good? Would it be more performant than MSAA?

I am right now leaning Vulkan (first time diving into graphics programing apart from unity shaders) and at my current level I do not actually know how to do AA so I thought asking would be better and maybe when I learn how to do AA implement this idea.