A repository group is the recommended way to expose all your NuGet
repositories from Nexus to your users, without needing any further
client side configuration. A repository group allows you to expose the
aggregated content of multiple proxy and hosted repositories with one
URL to your tools. This is possible for NuGet repositories by creating
a new Repository Group with the Format set to
documented in Section 6.3, “Managing Repository Groups”.
A typical, useful example would be to group the proxy repository that proxies the NuGet Gallery, a NuGet, hosted repository with internal software packages and another NuGet, hosted repository with third-party packages.. The configuration for such a setup is displayed in Figure 16.6, “A Public NuGet Group Combining a Proxy and Two Hosted Repositories”.
Using the Repository Path of the repository group as your NuGet repository URL in your client tool will give you access to the packages in all three repositories with one URL. Any new packages added as well as any new repositories added to the group will automatically be available.