@
jindroush - naybe you could input your list into the
Import List plugin, possibly after making it into a csv file. It will do the matching on author and title, with provision for fine tuning by hand - the end result is a set of Marked books, which can be added to a
Reading List.
IMO Reading Lists are a better alternative for creating arbitrary lists of books, because they don't pollute your book metadata with arbitrary classification codes (tags or similar).
If the list results from doing a content search on the library using a search tool such as File Explorer's Search, Agent Ransack, Copernic, X1 etc, you could use the
Drop Search Results plugin to Mark the books.
BTW - threads are never closed at MR, unless the posting guidelines are contravened - eg advocating piracy. You never know when someone will turn up with a better solution, which may not help the OP, but could be used by folks facing the same issue at a later point in time.
BR