Customising Datamodel of (seeded) Sales Order Report

Summary:

How can we customise the Datamodel of the (seeded) Sales Order Report?

Content (please ensure you mask any confidential information):

The Sales Order Report is triggered from the Actions Menu in Order Management Screen.

The report getting executed is /shared/Supply Chain Management/Order Management/Sales Orders/ Sales Order Report

The datamodel which is linked to this report contains a fixed XML.

Customising the report template is possible. But how to customise the datamodel ?

I'm aware that this question was already raised earlier in this portal and an idea was raised as well.

But maybe there is any update , best practice on how to customise the datamodel for this report?