vSphere Replication prevents you from resizing the virtual machine disk files during replication. If you used replication seeds for the target disk, you can resize the disk manually.
- Stop the replication on the source site.
- Resize the disk of the source virtual machine.
- On the target site, resize the disk that is left over after you stopped the replication.
- Configure the replication on the source virtual machine and use the resized disk on the target site as seed.