Swift Remote repositories are currently only supported as Smart Remote repositories. Artifactory is the only Swift registry available today, so you would not be able to proxy other remote resources.
Please note that Swift remote repositories can only connect to registries that utilize the swift protocol. URLs such as swiftpackageregistry.com are considered HTML catalogs, since they do not host any actual packages and simply point to a third-party Git repository.
A Remote Repository defined in Artifactory serves as a caching proxy for a registry managed at a remote URL. Artifacts (such as .zip files) requested from a remote repository are cached on demand. You can remove downloaded artifacts from the remote repository cache, however, you can not manually deploy artifacts to a remote swift registry.
Remote Repositories enable you to proxy and cache Swift packages.
To define a remote repository to proxy a remote swift registry:
In the Administration module, under Repositories | Repositories | Remote, click New Remote Repository.
On the New Remote Repository page:
Set the Package Type to Swift and the Repository Key value.
Specify the URL to the remote registry in the URL field.
Click Save & Finish.
Setting up a Virtual Repository