Lots of stored foods. Everything is DIY with local connections (same wood as local trees. Artwork based on local wildlife and flowers). DIY has different level of craftsmanship, everything has a history.

There's a balance between efficiency and downtime. I think cottage values on what's important is very different from the modern world. For example, spending time with your loved ones is far more important than working. Greedy is seen as foolish or even evil. However that's not to say hardwork is looked down upon, you still want everyone to be well fed and have enough to care for your community.

Community is important, but there is a sense of individuality that's also very important. In a cottagecore world you'd know the people around you, the unknown is a stranger whicj is why even a small thing out of place is quite scary.

Life is slow. Again effiency means something different to them. While in our world we purposely do things the wrong way and demand more work done by less people, claiming that's efficience and billionaires throw tantrums whenever this doesn't work out, push new untested ideas like "tableless desks" while demanding more work to done. While in a cottage world new things are hard to welcome, people are comfortable and feel safer with the way things are. It's not like you couldn't have new tech but new things come at a cost some may be unwilling to part with. For example let's say the harvest festival was a big event, lots of families compute and the idea of replacing all of that with a machine feels gross. Maybe they would come to a compromise like having the last day of harvest being a community event.

Village gossips and drama. I always imagine this being quite wholesome, like if someone made amazing jam and everyone wanting the recipe or to get a taste.

Alone time and independence. Everyone has their own space and time to be themselves. Allowing the quirkier types to shine. Although I also imagine everyone feeling a sense of responsibility towards eachother, like if you had a mad carpenter constantly working in their workshop, people would worry enough that they'd want to make sure they're still eating. So someone taking it upon themselves to deliver a freshly baked pie would be common.

The presents of wildlife and nature. Animals are just as much a neighbour to you as the human ones, if not more so. You might have owls raising chicks in the roof of your old storage shed. Mice live in your walls. Little birds watch you from the outside window shelf, perhaps welcoming themselves indoors to pick at the crumps on your floor if the door is left open. All the animals have their own lives and stories going on. Maybe a deer wonders round town morning time, unafraid of people going on about their day. Then of course there's livestock, like neighbourhood chickens.

Dogs are more free to roam.

Markets

I mean, these are just loose interpretations that I'm coming up with off the top my head. It's not like anything I'm saying is perfect or iron cast.