Since OpsMan v3.0.33 a new feature to specify serial numbers have been added. More information about this feature is available in KB Adding serial numbers in Tanzu Platform for Cloud Foundry's Ops Manager
Operations Manager Settings
OM tool does not support configuring serial numbers in OpsManager settings yet. The serial numbers feature is optional and at the moment can be configured via OpsMan UI or API. The API docs is https://developer.broadcom.com/xapis/tanzu-operations-manager-api/latest/serial-numbers/
This KB will be updated with version of the OM tool that supports this feature.