There is no built-in feature for that, reports are not exportable, unfortunately. The closest you can get is using the Better Excel Exporter app.
With this you can implement custom reports in Excel, so nothing prevents you to re-create those that are available in Jira's web interface.
(Discl. I'm a developer of this app.)
Hi All! We’re excited to share the launch of an announcement banner that lets Jira site administrators communicate directly to their users across their Jira Cloud instance. ...
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