can we still Duplicate GWEN books when we finish them? (Like Hero's Handbook)

can we still Duplicate GWEN books when we finish them? (Like Hero's Handbook).
and how i can dupe them?

Once. If you want to get another book to turn in, you have to redo the quests again. The 1 time 'pay to fill in' was for people who had turned in a book before the reward was boosted. This allowed them to get the significantly larger reward without having to redo everything. Those that did not turn in a book before the change just got a lucky bonus.

Lol you can't dupe books sadly^^

You can't duplicate the books, but you can get a new empty one. You still have to redo everything though.

You can pay the guys you turn the books into 100g per page. They will only fill in the pages you have completed without the book in your inventory when you do those quests/dungeons. If you complete your first book 100%, turn it in, then get a new book, you can pay 100g per page to get a new book completely filled in. You can only do this once though. After you turn that second book in, the 3rd requires you to actually complete the quests to get them filled in.