Quoted from hub(1) manpage:
Use one of "https|ssh|git" as preferred protocol for git
clone/push.
It seems that ssh can only be used for clone or push commands.
So is it possible to use ssh to identify the user and run other command like hub create?
Short answer: no. The GitHub API is only accessible over HTTPS.
Long answer: https://github.com/github/hub/issues/1644#issuecomment-359002547
Thank you!