Yamato's character arc could be to abandon the Oden impersonation and not try to emulate his choices.
Or maybe learn from Oden's mistakes at least, since Oden leaving the country made room for Orochi and Kaido to seize control in his absence.
Yamato representing a Guardian Deity of Wano through the DF ability could hint at her ultimate decision to safeguard it, and in case Momo joins as a cabin boy, keep it safe and ready for his return as the proper Shogun when the time has come after his coming of age journey.
Or maybe learn from Oden's mistakes at least, since Oden leaving the country made room for Orochi and Kaido to seize control in his absence.
Yamato representing a Guardian Deity of Wano through the DF ability could hint at her ultimate decision to safeguard it, and in case Momo joins as a cabin boy, keep it safe and ready for his return as the proper Shogun when the time has come after his coming of age journey.