1. It depends on how many files/folders youhave. If there are millions of files, it will take time.
2. No, fpolicy is configured on SVM level, you can create fpolicy policy, set of events that need to be monitored and for which of the monitored events notifications must be sent to the designated FPolicy server.
https://docs.netapp.com/us-en/ontap/nas-audit/steps-setup-fpolicy-config-concept.html