“Dunno in the sunny city” and “Dunno on the Moon”. The latter is rather an anti-capitalist satire.

I really love them and managed to buy both books with the original illustrations for my kid.

To my recollection, the former was a post-scarcity utopia that, like in most children's literature, east or west, didn't go too deep into the details (with the main moral of the story being 'don't be a dick to people'). I don't think it was particularly political.

The latter was satirical anti-cap propaganda.

Kinda true. The Soviet children knew there was no communism in the SU. But the book could give a clue on how it's supposed to look like.

You have children books being critical on Capitalism here in the West too.