My response to the question if there is punishment for those who mistranslate is straight from what was said concerning the matter in the Bible:
For I testify to everyone who hears the words of the prophecy of this book: If anyone adds to these things, God will add to him the plagues that are written in this book; and if anyone takes away from the words of the book of this prophecy, God shall take away his part from the Book of Life, from the holy city, and from the things which are written in this book.
Revelation 22:18-19
We see what the Bible has proclaimed concerning those who add to or subtract from the word.
Furthermore:
But even if we, or an angel from heaven, preach any other gospel to you than what we have preached to you, let him be accursed. As we have said before, so now I say again, if anyone preaches any other gospel to you than what you have received, let him be accursed.
Galatians 1:8-9
It is evident that there is a curse waiting for anyone doing such....... So the answer is yes, there is punishment for those who mistranslate the Bible.
Visit the Link below for more clarity.
Thank you.
The bible is the word of God so no one should add or subtract