user1691: If I have secp256k1 keypair that is widely known, like a Bitcoin address, can I convert that into a Ed25519 key pair such that someone could access a .onion address in a deterministic way?

user52021: The bitcoin key could sign a message containing the onion address. There are several other alternatives but there isn't any way to do this without the key holder producing a message of some kind.

1691: <p>If I have <code>secp256k1</code> keypair that is widely known, like a Bitcoin address, can I convert that into a <code>Ed25519</code> key pair such that someone could access a .onion address in a deterministic way?</p>
 52021: <p>The bitcoin key could sign a message containing the onion address. There are several other alternatives but there isn't any way to do this without the key holder producing a message of some kind.</p>
