In article .com,
wrote:

The brick probably has to be covered in concrete to be reasonably water
tight.
If the parging below the crack is sound, I'd leave it be.
Trim along the line of the crack for a smooth finish.

I think I would leave the paint and let it weather.
That's not beautiful, but I worry about chemical reaction with the
stone.

TB

so what kind of concrete should I cover the brick with? Is there a
specific parging concrete? I'm totally new to this, and I can't find
much reference to concrete for parging online.