I would recommend updating the firmware on both printers
The ^PON should make everything print the same direction. The question is what do you consider right side up? In ZPL, right side up (Normal rotation) is with the top of the label coming out of the printer last. This is opposite direction from many printers. It makes it so that if the printer is hanging from a belt or strap, a second person looking at the printer will see the printout hanging right side up.