The "No Library" part seems up self explanatory meaining we won't get any of the books associated with Essentials.
But if you check out this comparison https://connect.faithlife.com/now-connect-compare Now features and Essentials you will see that the two plans march in lockstep down the page feature for feature. And i see what appears to be lots of books in the Now column. So what does "No Library" really mean?