Context: we have three JIRA projects and one Confluence site that needs to be migrated to a new account. Your mental model is as if a business unit is being sold or spun off or something. The origin account has 100 or more Jira projects, dozens of Confluence sites, and 100s of users. The target account will much smaller. Both are cloud instances with different plans.
The closest match that I've been able to find suggests doing a full backup/export of the origin site and then delete what isn't needed, but since we'll be retaining something like 1% of the content and users, that seems extremely inefficient.
Are there better options?
