When we say reverse migration it means migration work load from cloud to on premises.
To perform reverse migration you need to log in to your on premises vCenter and click on HCX plugin.
Go to Migration tab and click on migrate virtual machine.
Now you need to tick mark reverse migration. Once you select reverse migration , your cloud vCenter inventory will be populated to you.
Now you need to select virtual machine which you want to bring back to on premises and define migration option shown in below screen shot. You have to specify the destination cluster, destination datstore , Type of disk provision and most important is type of migration (vmotion or bulk migration) and select or verify the correct VXLAN or VLAN where you want to place your machine. Once you define all option click next.
Review and click on finish to start migration.
Monitor the task till it gets complete.