As far as ESI is concerned, they are covered by the ESI Act, and contributions should be paid at the place of their work, i.e., in India. For EPF, the same rule applies, but I doubt if they fall under international workers. If they do, their contributions will not be limited to 12% of Rs. 6500, but the entire PF qualifying amount (Basic + DA mainly) paid in India will attract PF. However, I am not sure whether persons of Nepalese origin who have migrated to India for permanent settlement are considered foreigners whose details need to be provided to the nearest police station, etc. If they are free to work in India, they will have the same status as any other PF member.
Regards,
Madhu.T.K