The task is to decide on and implement the best way to handle links to external binaries during import/export, and implement that method in the import/export tooling.
Currently, when binary resources are stored externally to Fedora using the "Content-Type: message/external-body" redirection feature , an empty binary object is created in the repository. When the export tooling is used, a copy of this empty file is serialized to disk.
There is consensus that this is the best approach. Currently, the verification tooling reports a mismatch between the empty binary stored on disk and the redirect to the binary stored online. If it is useful to store the placeholder binaries on disk, then the verification tooling should be tweaked to skip over and not attempt to verify empty binary files.
Once this task is complete, a related task  is to adjust the verification tooling to handle resources with this extension.