External or federated storage that doesn't proxy through Nextcloud server?

Currently on 14.0.3, nginx 1.14.0, php 7.2.11, on top of Arch.

I don’t find this information called out in the documentation, but I am looking for a method of storing data on a second server that doesn’t cause the Nextcloud instance to proxy data transfers when the files are accessed via Nextcloud.

I would expect something like S3 external storage to have a request fulfillment data path of Client req -> Nextcloud -> S3 -> Nexctloud -> Client. What I am looking for is a method that will have the Nextcloud instance handle authentication and just redirect the client to pull data from a secondary source. In this way it is transparently served to the end user via the Nextcloud interface, but the data is not actually coming
through the Nextcloud server.

Also specific to my config, I don’t want the Nextcloud instance to store any files so Federated Storage seems like it wouldn’t be the solution as it would be on the end user to manage where their files are stored.