With all SSH algorithms, the SSH client and the server agree on the best algorithms they both support as part of the handshake.
I have a question for the hmac algorithm. Is it possible to choose specific algorithm while connecting via SFTP? Or is it necessary? What is the logic behind it? Is WinSCP trying all the options it has, while establishing the connection? I can see that our version (5.19.6) is supporting multiple algorithms and we need a specific one from them to connect to the some of our customer. So if WinSCP is trying all the supported options while handshaking and handshake with the supported one on the server (which is very logical) then we don't need to specify any algorithm.
Also there is no option for the cli documentation to specify the hmac algorithm?