Well for me, vRA (vRealize Automation) and Ansible are doing the same job.
vRA is here to automate the provisoning of whole platforms, from VMs deployment, network conf, to app deployment, etc... With the possibility to have a portal to propose users to do it based on blueprints.
Ansible module for VMware is, in my opinion, the free / open-source alternative to vRA, (without the buit-in portal)
An Ansible module for vRA is a bit of nonsense and I don't think will be available.