It depends. We can only work with the metrics the arrays provide. When it comes to shares, quotas need to be in place for share-based capacity metrics.
However, if you can map your shares 1:1 to the underlying container (such as flexvols in case of ONTAP) you could use the metrics on the flexvol level instead for chargeback.
But if you have multiple shares in the same container/flexvol, which technically is possible afaik, there's no way to break the capacity metrics down on a per share basis without the quotas.
See, this is not a limitation of OCI but the technology in use.
Hope this helps.