Hello Ayush Singh. Thanks for contacting Careers360 and we hope we will be able to answer your query.

First, I would like to direct your attention to this link for the latest Hindi medium books offered by Arihant Publications:

• https://arihantbooks.com/hindi-medium-books_549

Now, we expect the books to come out at least by December. But, this is only tentative because I am not an official from Arihant Publications. 

But, please expect the books updated for JEE Mains 2019 by January at least. But, one thing you can do. 

But the 2018 edition book and get this years JEE Mains paper from one of your friends. It has questions in both Hindi and English languages. Problem solved! Why to wait for one year?

Practice it on your own. You can also ask for explanation of the solutions from some coaching centre teachers.

Hope this helps you and all the best!