If you're having trouble finding a Pnach file or are unsure about its legitimacy, consider reaching out to gaming forums dedicated to Persona or Atlus games. The community might have official or unofficial solutions that meet your needs.
Search for P3FES-cheats or pcsx2-pnach-collection on GitHub. These are often maintained by modding communities who version-control their codes. This is the safest option if you are familiar with using raw text. persona 3 fes pnach file download