Owning a physical copy of WE9/PES 5 is legal; downloading it from unofficial sources is a gray area (abandonware). I do not endorse piracy, but I can guide you on finding legitimate or safe fan-made patches if you already own the original game.
Security experts consistently rank video game piracy as one of the top vectors for malware. Here is what cybersecurity firms found in 2022–2023 regarding "classic game" downloads: descargar winning eleven 9 para pc actualizado 2023 verified