STM32H753I-EVAL board USB OTG HS connection

[JZou.2]

The PHY chip for HS is USB3320. On the SCH part of UM2198, PIN32 of USB3320 is optional connect to MOSFET. Is it for power on sequence purpose? I can not find the power up sequence requirement for this.

Is it requirement of H753's HS OTG?