This replaces the configuration of files per ssh match block, as well as the need for keychain. See: https://keepassxc.org/docs/KeePassXC_UserGuide#_ssh_agent
This fetches all new host keys when connecting to an existing host. This allows to fetch newer keys and prevents a question if old keys no longer exist.
Make public what is already known to the public. Also define keys in variables for easier maintenance. Some hostings still don't support ed.
Configure ssh, use git-crypt to crypt the configuration. That way no information like domain name, ip, port, username, etc. are exposed.