While cloning or attempting to restore a snapshot between instances from different Aura projects using the Aura API, you will receive the following message:

"errors": [
{"message": "Cloning across tenants is not allowed",

"reason": "source-db-not-in-same-tenant"}
]

This behaviour is expected as cross-project actions are not allowed in Aura.

If you wish to clone instances across projects, 

1. Create a new snapshot or pick the latest one from the source instance
2. Download the snapshot locally using the Aura Console
3. Upload it to the target instance using the Aura Console

https://neo4j.com/docs/aura/managing-instances/backup-restore-export/