I have called Airbnb, the answer was not completely clear to me to be honest:
Basically the representative said that the person who leaves the review (Host or Co-Host) will be the one that gets the rating from the guest.
This is his reply, i’m not sure he is 100% correct, but it’s the best we have for now:
“Regarding your question, if you receive an Instant book reservation, both you and your host will have the option to leave a review to a guest. The one that leaves a review to a guest is the one that will have his review published on the profile.
If your host admin leaves a review to a Guest, his evaluation will be shown on the host admin profile and not yours and even if it is a good or a bad review, it won’t impact your hosting ratings nor your Superhost status”