I noticed that (which is quite contradicting) it is hard to buy crypto and Blockchain books with actual crypto. Hence, I want to sell them for crypto.
Now that you've mentioned it, I do not see altcoins creators publish any book detailing their project. I only see whitepaper
Is there a demand for it?
I doubt very much that there is a lot of demand, if it had much demand we would probably see it here in the forum. But you can continue to do research, because it may be the case that people are not doing books because they know they will not have a platform to sell and be paid in cryptos