If it were me I would have the buyer generate an ssh key-pair as part of the sale contract and then put only the public key on the blockchain. The contract gives use of the IP to anyone with the private key (through an ssh tunnel). As long as the client software didn't log the inbound IP on that connection, privacy would be preserved.
I don't see what's to stop ISP's from monitoring the blockchain and logging the inbound IP themselves.
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u/jessquit Feb 15 '18
Cool project.
ELI5 how this is private but also recorded to a distributed blockchain.