Best practices for disaster recovery recommend that to be safe with their backups, organizations should follow the '3-2-1' rule, that is, keep 3 copies, 2 media types, 1 copy off-site. Veeam Backup & Replication allows you to configure Backup Copy Job to have at least two independent copies of backups, whether onsite or offsite.
Moreover, as long as you have has two separate storage devices, the tiered approach also makes sense. This means you can configure a fast, small storage as primary, keeping minimal amount of copies for best RTO (these can be the last 7 - 14 copies typically used to complete 90% of restores). A storage with larger capacity can be used as secondary, keeping a lot of restore points (with GFS) for best RPO.
You can use deduplication appliance as a secondary storage; when planning for storage, remember about the right balance for your environment — between higher deduplication ratio and better I/O performance. For considerations and recommendations, please refer to Deduplicating Storage Compatibility section of this guide.
Copied backup files have the same format as those created by backup jobs and you can use any data recovery option for them.
See also: How It Works: Backup Copy