A source volume can have multiple destination volumes. The destination volume can be the source volume for any type of SnapMirror replication relationship. You can fan out a maximum of eight destination volumes from a single source volume.
You should be able to follow up normal procedure by creating peering relationship between the source cluster and the new destination cluster and once that is accomplished. You can create the snapmirror relationship and initialize it in able to start the migration.
You would need to confirm that there is no current replication going on on that source volume during the step of the new relationship and make sure that the migration/replication does not conflict with any other operation done on that source volume.