Essentially you're talking about different levels of coverage.

As I understand it, sacked brick means that the mortar is roughly even with the surface of the brick, rather than being pushed back as is pretty standard here in the US.

Mortar wash is synonymous with a German Smear, similar to whitewashing, but done with texture instead of paint. It is more coverage than sacked brick.

Stuccoed brick is exactly what it sounds like: stucco layered over brick. Sometimes this is done with gaps to provide a look of crumbled plaster. Stucco is thick enough that, where it is applied, it completely obscures the brick.

I hope this is helpful!

Thank you! I love sacked brick but did not know the term. Lydia do you know if all brick can have this treatment?