As per powerCLI documentation,
https://developer.broadcom.com/powercli/latest/vmware.vimautomation.hcx/commands/new-hcxmobilitygroupconfiguration
In order ot migrate tags, the following attribute has to be included in new-HCXMobilityGroupGonfiguration cmdlet syntax: [-ReplicateSecurityTags < Boolean > ] -> "Specifies whether you want to replicate the security tags after the migration."