Without sigpatches, your Switch will install the NSPs but refuse to launch them or load entitlement signatures. Download the latest hekate + Atmosphere sigpatches (from the usual homebrew sources) and copy them to your SD card. Overwrite everything.
With this guide, your Pirate Warriors 4 experience will be complete—no missing characters, no error codes, just full musou chaos. Now go claim the One Piece (and all the DLC trophies). one piece pirate warriors 4 nsp update dlc work