Armoured evolutions are called "Mecha" forms/evolutions. Ancient people of Galar harvested metal produced by Meltan/Melmetal. Using this metal certain Pokemon unlocks "Mecha" forms.

Mecha Mewtwo will be revealed in Mewtwo strikes back evolution. Mecha Charizard, Lapras, and Flygon are real. Mecha Charizard is the dragon looking head on the wall of the fortress city on the Galar map.

The wolf/dog on the logo's is the "Lucario figure" of the games. Likely the most popular new Pokemon. It's based on the "Black dog" and is Electric/Dark. Same in both games. Big one to beat at dark gym.

Time travel plays a part in the story with future versions of some Pokemon making an appearance. Slightly different designs/typings. Legendary trio represents past/present/future. large nod to innovation and evolution. Present one is like Zygarde and not part of the story. Just post-game.

Region is actually based specifically on England, not the entire UK. The red brick city you see in trailers is Manchester inspired.

Grookey is a nod to Darwin and evolution theory. Hence ape for a UK region. Has the best final evolution. Sobble goes dragon, very English. Rabbit is football themed, probably has what will be the least popular final evolution.