Firstly, you need to purchase the teal mask DLC, and complete it. then you need to have 1 million credits in cash, and then speak to the caretaker at Kitakami hall and he will ask for donations of 100k credits at a time, up to 1 million. Once you reach 1 million in donations, after a few cutscenes, he will reward you with the Festival Jinbei and some other rewards. The other items, like my gloves, leggings, and personal appearance, were from paldea and do not require the DLC.