Trying to use onlykey-agent with ansible to manage multiple hosts in parallel or even serialy :
the agent requires pin chalenge for each host, thus making mass ssh impossible.
I suggess to add a feature to "unlock the ssh key" until a command has ended :
onlykey-agent identity@host --unlock-until-finished -- ansible-playbook play.yml
Enter the 3 digit challenge code on OnlyKey to authorize identity@host
..
ansible runs via ssh on host1
ansible runs via ssh on host2
...
basically this means having to enter the challenge once per command, not per host.