I can't find the button.
I don't believe there is an option to do anonymous peer reviews. But you can require peer reviews on a discussion, steps are how in How do I create a peer review discussion?
You will see the peer review option when the assignment is selected as a graded discussion.
Have a great day.
Were you able to find an answer to your question? I am going to go ahead and mark this question as answered because there hasn't been any more activity in a while so I assume that you have the information that you need. If you still have a question about this or if you have information that you would like to share with the community, by all means, please do come back and leave a comment. Also, if this question has been answered by one of the previous replies, please feel free to mark that answer as correct.
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