burnt veldt
this server doesn't offer support for pirated copies, and not just for the typical reasons, but also because of the challenges of providing support for non steam copies (without getting into too much detail, theres too many potential variations and a lot of mods/tools are designed for the steam copies of the game)
ill let you know right now so you don't waste your time but P5S already is particularly difficult to mod as is, so the truthful answer is that there probably isn't a solution to use mods without Aemulus. you'll have to buy the game or just play unmodded
ionic leaf