Reporting required in gst returns ?

Dear Experts

It is understood that supply under merchanting trade is outside the levy of gst.

So, is this required to be reported in gstr1 and / or gstr3b under the category of non-gst supply or exempt supply ?

If this is not shown in gst returns--  will this create a mismatch in turnover between gst and income tax records and hence invite scrutuny from either of those departments ?

Regards