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From what I saw, on Flutter there is no kind of review within the app for Android. I looked in other places and saw that for native there is this possibility, to ask for a review and basically what happens is a bottom sheet going up with the content of the Play Store to do the review with space to put the stars and the comment. As in the image.
You can search with some "keywords" whenever you need some kind of package on pub dev I found these results that can help you.
– murakami Kauê
Has the package "in_app_review": https://pub.dev/packages/in_app_review
– Romario Jr.