Hi,
I just completed Meta interview last week, no results yet.
I got a request from my recruiter now asking if anyone at Meta would give feedback on working with me. What are the expectations here? Also, why post interviews?
It's a positive sign meaning that they care enough about you to follow up and do some sort of reference check.
In terms of expectations: [Meta Hiring Process] Meta recruiters request references before submitting feedback file to review committee
Meta has always done this, but I think them asking for it is more pronounced now. I don't know if they're only doing it for candidates that have done well or all of them, but I agree with Rahul in that it probably means that you did solid (at least "Weak Yes").
In short, the references help but aren't required. Check out this thread: "Can you please suggest me any names from Meta to put as references?"