There are some ROCS utilities
You can use them to Extract , modify in bulk and import.
https://bitbucket.org/reltio-ondemand/util-rdm-dataextract/src/master/
https://bitbucket.org/reltio-ondemand/util-rdm-dataloader/src/master/
Again this is not an end to end straight forward solution, but better than fully manual effort.
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Gowthamprabhu Sivaraj
AstraZeneca
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