Vault Enterprise License on different Cluster

Is it possible to use the same Enterprise license on different Clusters?
(examples, production and development)
Or once inserted, it activates via the internet or so, and is linked to a particular cluster?

Vault does not phone home to validate licenses.
You can apply the same license to multiple servers/clusters (at least as of the time you asked).

(Technically, that is. Refer to your contract wording or HashiCorp representative regarding whether it is contractually allowed.)

Yes! Thank you for clarifying!