You mean review apps like this -> https://apps.shopify.com/product-reviews ?
It's not a feature of a review app I've thought of or heard of. Not to say it doesn't exist. My most favourite and recommended review app is Judge.me https://apps.shopify.com/judgeme. I suggest you contact support to see if the feature you're after is available (then share it here of course so others know.)
We've seen this feature before. We developed it in our app for another ecommerce platform.
To be honest we didn't find a great deal of demand for it from merchants or customers, unless it was a high repeat business type of store.
In saying that, we'd be interested in finding out some more about your's, and any other merchants requirements for a feature like this to see if we can do something to help out.
Just drop an email to firstname.lastname@example.org
HelpfulCrowd Review and Q&A APP