Use case: 

You need a burst to deliver an external report in the body and also duplicate the same report as an .xls attachement.

Obstacle: 

External reports can not be sent as .xls file, only as .csv or .pdf

Decision: 

You'll need 2 reports (simple report and external report) + a burst using an email template that will send only external reports in the email body and attach .xls, .scv, .pdf files

The steps to be followed to reach this goal:

• Create a simple report (Standart Report) and collect data. Then, go to Report Distribution tab and choose "all rows" from "Show in Email" drop down and "XLSX" from the "Attach to Email" drop down. Save & Publish the report

• Create an External Report that will be sent in the email body. Go to Configuration tab and remove the tick from Collect additional files. When removed, it won't send any .csv attachments along with the external report. Save the external report.

• Create a duplicate of "Burst - Any Image Size wide" Email template and name it "Any Image Size Ext Reports only in boby"
• Go to Section Templates tab and add 1 line of code if ($element['element_type'] != 'external report') continue;

• Save your new Email Template
• Use this template in your burst

• Save & test the burst ("Send now" button).
• The mail with your burst will look like that