You can always manually edit the pcf file, there is "Edit PCF" button on isometric generation screen. But there is no pcf statements or commands to show X-Y-Z compass on isometric drawings, you can try to set your own backing sheet with X-Y-Z compass previously drawn by AutoCAD.
Regards,
Shawn Zhong
COADE, Inc.
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Shawn Zhong
CADWorx & Analysis Solutions
Intergraph Process, Power, & Marine