This article explains whether it is possible to migrate historical data of objects (metrics, properties, events, etc.) from one VMware Aria Operations instance to another
Aria Operations 8.x
VMware Aria Operations does not support migration of historical monitoring data across different instances. However, you can export and import content items such as dashboards, views, reports, and other configurations into the new Aria Operations instance.
For detailed guidance, please refer to the following documentation on content management