DVN 3.x supported a feature called "harvesting" wherein metadata for datasets hosted elsewhere could be made discoverable/searchable within Dataverse while the original files remain hosted on the remote site. When we upgraded the Harvard Dataverse from DVN 3.x to 4.0 we put all the datasets we had harvested in the DVN 3.x days at
https://dataverse.harvard.edu/dataverse/harvested where you can see how the metadata is available but the files themselves are elsewhere. We haven't yet added the harvesting feature to Dataverse 4 but we are working in it at
https://github.com/IQSS/dataverse/issues/813 . Comments are welcome on the Functional Requirements Document linked from that ticket!