Currently, the ability to copy workbooks between workspaces is still in development. While you can create blank workbooks and add multiple tables to them, the feature to duplicate workbooks (which would preserve relationships across tables) is planned for future releases.
Source:Clay workbooks
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Hi Nicolas, thanks for reaching out. Taking a look at this now! You can share a workbook as a template from one workspace to another, but you won't be able to transfer over the workbooks contents. Let me know if you have any other questions on this!