Depths: Big Sudama trading rules

[Mr.America]

So, trading with the big sudama in the depths seems to follow some rules:
equipment + fists = unchanged equipment but grace changed to takejiro + any fists no +values rerolled effects.
equipment + helmet = unchanged equipment but grace changed to sukunahiko + any helmet no +values rerolled effects.

Are there any other special rules applied to big sudama in the depths? Something like soul core + kusarigama = same soul core but with ninjutsu power + rng kusarigama?