Hold on let’s do this properly:
Paddington - regrettably a monarchist but in that specific immigrant way. The only actual immigrant on the list. May possibly just be a monarchist as part of the processing stage and is also canonically a child.
Winnie the Pooh - is canonically a stuffed animal, I genuinely don’t think he has this level of thought/agency and is not written as such. The real living breathing animals (owl, rabbit) are not just monarchists, but actively and cruelly bourgeois.
The Velveteen Rabbit - doesn’t wear a waistcoat but not a monarchist either.
Angelina Ballerina - a monarchist and a bit of a little bitch tbqh
The Brambly Hedge mice - really unclear. But like worryingly unclear. Clearly some kind of caste system in operation (lords and ladies) but not capitalist or explicitly feudalist either, it seems a thin overlay over their real political intentions: incredibly intense cheesemaking forming the backbone of a post-scarcity economy.
Beatrix Potter / Peter Rabbit - monarchists.
Richard Scarry - actually I can’t make a call on this one
Animals of Farthing Wood - I … don’t know.
Wind in the Willows - Toad’s a fucking Tory, but I feel like the Water Rat is kind of a comrade
Watership Down - unfortunately many of these rabbits are fashy, even the ones you like. Ursula le Guin said it, not me. They wouldn’t walk away from omelas. However, they touch a lot of grass - enough grass to not be interested in the house of Windsor - which is a point in their favour.
Redwall - monarchists, though not for the British monarchy. and also, somehow, Mouse Anglican verging on Mouse Catholic. Worrying, fascinating.
Oakapple Wood - monarchists
Hobbit - not a woodland creature but wears a waistcoat and is sympathetic to Thorin, Aragorn. Provisionally extremely monarchist and the very earliest interpretations of hobbits appeared to think they are somehow bipedal rabbits, which pissed Tolkien off.
Rupert Bear - British bear in clothes attributed partially for the decline in the usage of the name Rupert - but I don’t know a thing about him
The Highway Rat - all Julia Donaldson creatures lick the boot that crushes them, even the highway rat. Possibly not the Gruffalo. The Gruffalo however is the most naked that anyone has ever been, thus not an animal that would wear clothes.
The Narnia creatures - don’t all wear clothes, but THE definitive monarchists
Fantastic Mr Fox - not a monarchist. and in the wes Anderson film is not even British although the farmers and setting are (brilliant artistic choices, especially including an excellent but fucking random possum that calls the entire ecosystem into question: ultimately these are North American animals subverting and undermining the British landowners in a strange political statement whose intentions and direction are unclear.) Not monarchists, but what?
I also asked my own small British child to name more notable creatures in waistcoats, and after suggesting the obvious (brambly hedge, Angelina) they said, devastatingly, “viruses,” and when I delicately questioned what they meant by this, pointed out that viruses have a protein coat. Thus:
Viruses - possibly monarchists, wear coats, and present in children’s literature as exemplified by the Usborne “See Inside Germs.” Ultimately more data is needed.