You cannot override the OOTB pzStageProcessesList section rule (Pega-EndUserUI:07-10-17), since it is a Final rule. You could save pzStageProcessesList using a different name into your ruleset and then update all the references accordingly.
Could you please raise an enhancement request on Pega to make it available. Any rule referred in end user portal should be available. I don't see a reason for this to be a final rule. Could you raise an SR explaining what you intend to do.
Thank you for helping us identify a product enhancement. An enhancement has been submitted on our internal portal and the ID is listed under the Related Support Case Number field in the original post above. Please contact your Pega Account Executive for next steps.