This is currently the most accessible way to play modded Bloodborne if you don't have a jailbroken PS4.
Before downloading any mods, ensure that your version of Bloodborne matches the requirements. The CUSA00900 version, along with version 1.09, is compatible with a wide range of DLC mods. This can usually be verified through the game's properties or details section on your console. Download Bloodborne v1.09 -DLC Mods- -CUSA00900