Comment 2 for bug 1685022

You appear to have manually removed /etc/ssh, so you'll have to recover from that manually too. Reinstall the openssh-client package as follows:

  sudo mkdir -p /etc/ssh
  sudo dpkg --configure openssh-server
  sudo apt install -oDPkg::options::=--force-confmiss --reinstall openssh-client

I've committed a change to my Debian openssh repository to ensure that /etc/ssh exists before trying to create sshd_config within it, which would have helped somewhat with this.