1. The documentation you are looking for is Type-C and Power Delivery SPEC. Whatever MOS FET control with enable and disable is aim to follow those SPECs.
2. For your questions:
a. Control sequence is based on what's role of Type-C port is going to support. For example, Power source role enable:
a1>> Before attach Type-C sink, MOS FETs shall be disable for achieving Safe0V.
a2>> Attached. And then, Rp and Rd is present. And Type-C enter Attach mode. MOS FETs shall be enable for achieving Safe5V.
a3>> Enable VCONN if it have capabilities. And send SOP' for cable discovery identify.
b4>> Discovery SOURC_CAP on CC.
b. For OVP.
>> When OVP is occurred. MOS FETs shall be disable for being deleted OVP event. And then send Hard Reset and Altert for this case.
>> If OVP occurred over re-try times (3 in default firmware), The Type-C port need plug out and in to resume Type-C Power Delivery negotiation.
c. When connecting Quick Charge / Apple Charge, Apple Charging is serving first. And then BC1.2 serials (BC1.2, QC2.0, QC3.0, AFC, and so on.)
d. You shall refer Type-C and Power Delivery SPEC to get details.