It's up to you how you want to do it. You both could sit down and add in your own details about the review, or if you think the two of you have very different opinions on the product (one thinks it should be 1 star while the other things it should be 3, for example), you could write two different reviews. I always stick with writing one review instead of having two so then it's easier to see all of the information in one place instead of me writing something and my boyfriend writing something.
If you're asking if there is a specific feature on EF that allows you to write two different "reviews" and meld them into one, then no. However, we have some reviewers who do the "He Said", "She Said" format.