ExperienceBundle is a feature that allows you to retrieve, deploy, create, update, or delete an Experience Cloud site's metadata definition in a single API call. Some of the key features of ExperienceBundle are:
ExperienceBundle enables creating experiences across orgs. You can use ExperienceBundle to move your site's metadata from one org to another, such as from sandbox to production.
ExperienceBundle provides editable community metadata in a human-readable format. You can use ExperienceBundle to edit your site's metadata in JSON or XML format, which makes it easier to understand and modify.

To enable the installers to collaborate with their co-workers and UMS staff, UMS needs to enable Portal User Visibility. This is a user visibility setting that allows portal users to see other portal users who have the same role or a role below them in the role hierarchy. This also allows portal users to see internal users who are above them in the role hierarchy. Portal User Visibility can be enabled in the Sharing Settings page in Setup.

This option allows UC to control the access to the partner application form and ensure that only qualified partners can apply. Token-based referral links are unique and expire after a certain time, which adds an extra layer of security. Creating an app for the internal team also allows UC to track the performance of the referral program and reward the existing partners accordingly1

An External Account Hierarchy is a feature that allows you to create a hierarchy of accounts for your partners and grant access to records based on the hierarchy level. You can use an External Account Hierarchy to grant View access to cases created by child companies to their parent company.

Sharing sets allow you to grant access to records that have a lookup relationship to the same account or contact that the community user has. You can use sharing sets to share opportunities with partner community users who belong to the same account as the opportunity owner.
Criteria-based sharing rules allow you to share records based on field values. You can use criteria-based sharing rules to share opportunities with partner community users who meet certain criteria, such as region, industry, or status.