Do PMOS Reverse Input protect on ORed power rail
Yes, a PMOS can provide high-side reverse polarity protection. However, the way you have drawn your circuit is a bit backwards. You need to swap source and drain. See this question for a schematic.

Also, note that the gate-to-source voltage on the PMOS will be equal to the input voltage. So you need to select a PMOS where Vgs max is greater than Vinput max and Vfused max. Otherwise the PMOS may fail.