All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
If the manuals that you are requested to translate propagate cigarettes and aim to convince people to smoke and make them love it, then it is not permissible for you to translate them, because cigarettes are Islamically forbidden as we clarified in Fataawa 87196 and 81589.
Therefore, it is not permissible to help in it by any means especially in what propagates it and calls people to smoke it. Allaah Says (what means): {…but do not help one another in sin and transgression.}[Quran 5:2]
On the other hand, if these manuals and publications clarify the harms and disadvantages of smoking, and call people to quit it, then it is permissible to translate them; rather, this is considered as spreading goodness amongst the people and calling them to it.
Allaah Knows best.