AHHH ok so you enter x,z that makes sense now. I was just thinking in a 2d plane since you only enter two coordinates, and thinking in x,y made it look like it was mirrored. My bad.
I don't know if compass mods just arbitrarily choose the cardinal directions of a map, but our world's north is the -x value lol.
*now I see you mention x,z in the command line info. Wish I had read that first. As usual, I prefer to learn by bashing my head against things rather than reading the instructions.