What is the correct way to transfer server SSH keys to new clients?

Question

SSH

Let's say there is a server or several servers with authorization by key. On one of the working computers, the connection to these servers is successfully configured, everything works without problems.
And then another computer appeared, where you need to set up a similar connection. How is it customary to transfer the key in this case? Of course, without the option of temporarily disabling login to the server by key.
Do you need to transfer your public key through a machine that is already authorized on the server? And if there is also authorization by key?
Is it really only old-fashioned methods with the transfer of a public key on a flash drive? I feel there is a beautiful solution, I can't figure out which one.

Answer 1

The client generates its own key pair and sends you the public key by mail. Or on a flash drive, if you like.
Sending the public key is not dangerous.
But it is the client who should send the public key to you, not you who should send the private key to the client.