In the manga, Zero Two and Hiro have a different fate. They don't die. The plot takes them on a journey with various challenges but not to the point of death.
Yes, indeed. The Re:Zero manga exists and presents the story in a graphical format. It might have some differences from the original source, but it still captures the essence and excitement of the series.
As of now, the Edens Zero manga is not finished. The story is still unfolding, and fans are eagerly awaiting the next installments. There's no definite end in sight for the moment.