Question
What book has not most words written by Nietzsche when translated into English?
Answer
The Will to Power has books I, II, III, and IV:
- https://www.gutenberg.org/files/52914/52914-h/52914-h.htm
- https://www.gutenberg.org/files/52915/52915-h/52915-h.htm
If you combine all the sub-books of the The Will to Power, it is longer than Friedrich Nietzsche's other books.
Full disclosure: some people dispute The Will to Power on Gutenberg.org being complete. Others even say it may not count as a book written by Nietzsche in some contexts.