Shogunate Separation of religion
This mod separates Shinto and Japanese Buddhism, which were originally placed under the same religious group in Shogunate, by moving Japanese Buddhism into the broader Buddhist group.
While Shinbutsu-shūgō (the syncretism of Shinto and Buddhism) did result in a high degree of integration between the two faiths and peaceful coexistence in ancient Japan, this does not mean that either religion became a subset of the other. Their relationship was one of mutual influence, not hierarchy. Both Shinto and Japanese Buddhism maintained relatively independent clerical systems and religious rituals.
Japanese Buddhist monks also traditionally wore robes (kesa) influenced more by Chinese and Korean Buddhist styles, rather than the garments worn by Shinto priests. Unfortunately, the in-game kesa is only styled after Southeast Asian designs. It is hoped that in future major updates, robes and attire more in line with East Asian aesthetics—especially those of Japanese warrior monks (sōhei)—will be added.
P.S. A pointed criticism here for the EU5 dev team: forcibly categorizing Shinto under the Buddhist group was an ill-considered move. Even placing it under animism or Dharmic faiths would have been a more reasonable decision.
