Got fired from TCPi's social team so fuck it. Here you go.

The game is sort of like Monster Hunter, but a bit more open. Jubilife is your hub town, and you can fast travel to the five other areas, but each of those 5 areas can be walked to normally after you fast travel to one. They're essentially 5 massive wild areas (each significantly larger than Crown Tundra), including the Galaxy Settlement around Jubilife, which itself contains a smallish 'wild area'. The five areas are Obsidian Fieldlands, Malachite Marsh, Quartz Lagoon, Garnet Plateau, and Coronet Peak.

There are 6 Pokemon nobles, each of which has a warden minus Coronet Peak. They are as follows:

Obsidian Fieldlands: Kleavor (Bug/Rock evolution of Scyther)
Malachite Marsh: Salamoss (Grass/Ground evolution of Wooper)
Quartz Lagoon: Drifmarine (Ghost/Water evolution of Drifblim)
Garnet Plateau: Yetank (Ice/Steel evolution of Snorunt)
Galaxy Settlement: Qwazibonzai (Rock/Fighting evolution of Sudowoodo)
Coronet Peak: Matterelic (No type)

Matterelic is a Pokemon that guards Hisui a the top of Coronet Peak. In the past, it protected Hisui from a battle between Dialga, Palkia, and Giratina. Matterelic will be the only Pokemon in the franchise you won't be able to properly catch or own (somewhat like Gigantamax Eternatus, but you can at least catch Eternatus).

In the post game, there are missions where Matterelic will appear in Jubilife and call upon you for your help, which is how you catch Palkia, Dialga, Giratina, and other Sinnoh legendaries.

All the preevolutions of the Pokemon nobles have Hisuian forms.

Oshawott's final evolution is now Yamawott (Ground/Water)
Rowlett's final evolution is now Arbarrow (Steel/Grass)
Cyndaquil's final evolution is now Volquilno (Rock/Fire)