Possibly subverted in Redwall; on one occasion the Big Bad Badrang cuts a random minion's belt when he finds himself in need of a piece of cord, and everyone sniggers when said minion's kilt drops off. On two occasions, prisoners have suffered a Shameful Strip, which presumably wouldn't matter if they didn't consider clothing important in some way. In contrast, the cartoon show followed this trope; as well as most of the characters only wearing shirts, it showed Skalrag wearing variously only a cloak or nothing at all, and unusually depicted the female character Trefoil with an unclothed lower half as well.
Now, to be fair, a kilt is a kilt. They have more things in common with habits and (naturally enough) skirts than with trousers.
In the chapter-heading illustrations of Garry Kilworth's Welkin Weasels series, Montegu Sylver appears fully clothed including shoes, though he is apparently wearing nothing but a cloak on the cover illustration and is described in the text as not needing anything more than a cloak since he has fur. Scruff and Maudlin wear only jackets and hats. Bryony Bludd wears a full skirt which would not look out of place in the Victorian era the books are based on except for the fact that she is apparently topless except for a very large neck-bow. Mayor Jeremy Poynt fits the "jacket and hat" rule, with the addition of spats - but no shoes.
Koziolek Matolek, from the Polish children's book series of the same name, is a shirtless, anthropomorphic goat.
The Cat In The Hat, who wore a bowtie, gloves, a stovepipe hat and nothing else.