How can I import an existing Blockchain.info wallet to bitcoin-cli?
It's possible to export your private keys from Blockchain.info (a bit of googling showed me this: https://github.com/OmniLayer/omniwallet/wiki/Exporting-Private-Key-from-Blockchain.info-and-Importing-to-Omniwallet.org) and then import it in bitcoind using the import function (as described in https://en.bitcoin.it/wiki/Original_Bitcoin_client/API_calls_list)

Good luck!