As far as 'VAAI NAS – Full file clone' concerned, according to KB below, it is supported 5.x onwards and according to IMT all 9.x supports it. VAAI NAS Full file clone enables the Storage array host to make full copies of data (vmdk files) within the NAS array without using the ESX resources to read and write the data.
For cross-volume deduplication (IAD) : If this feature co-exists with IAD ? I don't see any issue here. Is your query .
Only caveats for IAD: All volumes must be thin-provisioned (space guarantee set to None) for IAD to work. IAD is not supported with NetApp Volume Encryption (NVE)*
*Starting in ONTAP 9.6, NetApp has included a new feature called NetApp Aggregate Encryption (NAE), which assigns keys at the aggregate level, hence encrypting all volumes within the aggregate. This not only simplifies encryption management, as there are less objects to manage, it also allows volumes to be encrypted and deduplicated at the aggregate level.
Did you ever test this successfully, and if so, how? I've just recently gotten my VMware hosts moved to an AFF-A300. Deduplication is enabled on the volumes and the aggregates and the VAAI plug-in is installed on the hosts. When copying a VMDK or cloning a VM *within* a NetApp volume, it's lightning-fast, but doing the same across volumes in the same aggregate is relatively slow. I don't know if I'm getting at least some benefit (reduced load on hosts, etc.) or if I'm getting no benefit.