Need to customize script report column as per following screenshot

[NCP]

I think, it is not possible.

How make merge columns on script reports

You cant change the report’s cells shape but you can still create the print format for the report and make merging for cells using HTML table tags You can check this link for how to do it https://frappeframework.com/docs/user/en/guides/reports-and-printing/print-format-for-reports