Yes! I can confirm that a second deployment succeeded on the second run. Great :-)
I was also able to delete the Local Engine with virsh. I'd like to point out for
reference, that this is only possible if a sasldb user is created like this:
# saslpasswd2 -a libvirt username
Password: ....
After that it was possible to do this with the created credentials
# virsh destroy HostedEngineLocal
# virsh undefine HostedEngineLocal
Glancing at the ansible output of the deployment process, the playbook seems to take care
of old local engines anyway.
Thanks again for your help Simone.