If you find a PC .sl2 save and want to convert it to CUSA18581 format:

If the "full" save was created with a modded PS4 (jailbreak), it may contain homebrew signatures. Your stock PS4 will freeze, crash, or potentially require a factory reset to clear the corrupted data notification.

Once you've recovered your save game files, transfer them back to your PlayStation console:

:

If you still intend to search for “Elden Ring save CUSA18581 ZIP full” on external sites (like Nexus Mods, The Tech Game, or console hack forums), always: