GST on freelance export service

Yes. Registraion is compulsory and you can either go for 18% payment of IGST and then refund or get LUT/Bond.

meaning of LUT

https://dgftcom.nic.in/exim/2000/gst/GST_Bond_LUT_Format.pdf

thnx,but one more query,
I have file original ST-3 on 14/08/2017 without carry cenvent credit of service tax and after that I have file revised ST-3 on 30/08/2017 for claiming of cenvent credit,so now I required to be file Tran -1 for taking ITC, so in your opinion can I mentioned original date instead of revised date e.g 14/08/2017.

It would be best if someone else replies to this. I am not confident enough