Sure, Kamado said that Sinnoh would be a good name for the region, but he's not a final authority, let me have my headcanon dangit.

Also sh no I didn't base most things besides the inter-Japan based regions off of their real life counterparts what are you talking about? shut up, i know it is extremely obvious.

If any spot says Spain in this chapter, it's meant to say Paldea but I made this before the region's name was revealed and just used the place it was based on as a placeholder.

~The Japan Based Regions~

⌲Kanto & Sinnoh absolutely hate each other. This is due to what Kanto did in the past. During and after the events of Legends Arceus, Kanto conquered the Orange Islands, Johto, Hoenn, and Hisui, and forced Hisui into changing their name to Sinnoh.

⌲Johto & Hoenn have okay relations. They're not good, but they're also not that bad. In recent years, their relationship has been improving.

⌲Hoenn & Sinnoh have good relations most of the time, unless Kanto & Johto are in another dispute.

⌲Kanto & Hoenn have great relations, to the point that Hoenn will side with Kanto during almost any dispute with Johto.

⌲Johto & Sinnoh have great relations. Sinnoh always supports Johto in their disputes with Kanto, both due to this good relationship and due to having extremely sour relations with Kanto.

⌲Most of the time, Kanto & Johto have extremely great relations. However, when these regions disagree, things go south very quickly, and the whole world gets involved.

⌲Kanto always ends up with the support of Hoenn & Kalos, whereas Johto always ends up with the support of Sinnoh & Galar.

~US & European Based Regions~

⌲Unova & Alola are apart of a larger federation of regions (United Regions // UR), and as such, don't have singular relations with the others, but rather shared relations. The UR does have internal relations though, and these two regions get along well.

⌲The United Regions had good relations with the former Kingdom of Alola, up until the UR decided to overthrow their government (and later annex them).

⌲In the past, Galar & Kalos had extremely poor relations and were often at war with each other. However, they now have close ties and work closely together. They are still petty, and often join in on disagreements on opposing sides just to be petty with the other.

⌲Unova & Kalos joined together when Unova + 12 other nearby regions fought for independence from Galar. This lead to the UR, which was founded by the original 13 regions, and Kalos being pretty close.

⌲This goes partly the same for Paldea, but relations were more rocky with UR due to Paldea's colonization of nearby regions, and later on, their dictator made things slightly rocky again, though they tolerated them. Kalos didn't have the same issue due to most of its colonies in the area being lost prior to the Independence of the United Regions.

⌲The United Regions used to despise Galar, but now are pretty close with them.

⌲Alola has always liked Galar, in a contrast to Unova.

⌲Paldea used to fight with both Galar and Kalos, but the three regions have since started getting along.

⌲All of them have good relations with the other 4, although they may favor one more than the others.

⌲Before you ask, yes, real life alliances carry over, so all of these regions are in an alliance together. The name of the alliance single handedly depends on what the ocean separating them is called because irl it's NATO lmao. This does also mean that all four of the Japan-based regions are Major Non-(NATO Equivalent) Allies.