GST REFUND IN CASE OF EXPORT OF EXEMPTED GOODS

We want to start new business of exporting of vegetables, coconuts, fruits etc which are exempted supplies as per GST. For making such supplies we will have to pay GST on RCM basis on transportation, on Custom Agency Charges, Input services etc. Can we get refund of all such gst paid if export made without of payment of IGST by filing manual refund application? Or we have to reverse such GST paid at time of filing of GSTR 3B?