Export To Excel Permissions With Security Groups but Splitting Out those Not Requiring Export

Good Morning

Hope someone can help please

I have a PBI report pubished to our Premium Workspace. Currently the users are in a Sercurity Group (as there are quite a few of them) The report originally did not require export to excel therefore this was disabled in report settings. I now need to enable this setting but for only a few of the users.

My question is,

• if I enable this in report settings to allow export to Excel and republish the PBIX file to the workspace,
• remove those requiring export permissions from their existing security group
• create a new one (splitting the users out)
• Give the new security group build permissions (keep build disabled for the original security group that export is not required) 

will the security group without build permissions be able to export too. Or would you advise creating a new workspace and adding a copy of the report with export permissions to that workspace and assign the new security group to that workspace

Hope this makes sense

Thanks for your help

Kind regards

Karen