There's a new "official" spot to farm PP in Feryana Wilderness on CH4, though I'm not sure if it's worth it over Zandora Chapel in CH4.
TP to Lookout Castle: Castle Gate Exterior port crystal and run to the waterfall in the map, there's 5 LV90 enemies there, a huge Living Armor (180 PP), a Great Living Armor (100 PP), a Living Armor (80 PP), a Great Death Knight, and a Ghost Mail (80 PP).
So that's a total of 540 PP, and you get the usual CH4 loot from the Death Knight, so 750 BO and some Starry Sky Scrolls, I don't think this is better than Zandora Chapel honestly.