It’s no secret that the “Pokemon” franchise is inspired by the real world. More recent areas, such as Kalos and Galar, takes cues from France and Great Britain, but the previous entries and their regions are based on Japanese geography. Eg, Sinnoh based on Hokkaido, and since “Pokemon Legends: Arceus” is set in antiquity-Sinnoh, the matching game takes from pre-modern Japan of Hokkaido, specifically its original inhabitants.
In “Pokemon Legends: Arceus”, the Jubilife Village is the only sign of “modern” civilization in Hisui. The rest of the game world is covered in untamed wilderness and mysterious ancient ruins. The only exceptions are the Diamond and Pearl Clans, who predate Jubilife, and their camps. These clans are not an easter egg as they are related to the real life Ainu people.
A long time ago, possibly from prehistoric times, the Ainu were the sole inhabitants of Hokkaido, which reflects the entire “Diamond and Pearl clan living on a land based on Hokkaido”. Ainu relies on Yezo sika deer for food and clothing, and the reverence of the Diamond and Pearl House Wyrdeer, an evolution of the Stantler believed to be based on the sika deer, and used its fur to make warm clothing for the winter. Coincidence or intentional? How about the new Ursaring evolution, Ursaluna? It’s not just a bear, but its new Ground typing and mountain-like body link it to the Ainu god of mountains and bears, Kim-un-kamuy.
Maybe we’re reading too much, but the Diamond and Pearl Clan and some of Hisuian’s Pokemon have too much of a connection to Ainu to be a mere coincidence.
https://www.looper.com/758509/easter-eggs-you-missed-in-pokemon-legends-arceus/ The Easter Egg You Missed In Pokemon Legends: Arceus