There is a exporter which does both export and domestic sale.
If any exporter is availing benefit of rosl scheme then whether he is eligible to take input of GST for domestic sales.
No ...you cannot.
Non-availment of drawback: The third proviso to sub-section (3) of section 54 of the CGST Act states that no refund of input tax credit shall be allowed in cases where the supplier of goods or services or both avails of drawback in respect of central tax.
Kindly Refer Circular 371/11/2018