Official home page seems hosts docs only starting from v2.3 and it mentions very few GCE related modules:

https://docs.ansible.com/ansible/2.3/list_of_cloud_modules.html

List of supported cloud modules.

Modules have mentions:

https://docs.ansible.com/ansible/2.3/gce_module.html

gce - create or terminate GCE instances.

New in version 1.4.

https://docs.ansible.com/ansible/2.3/gce_net_module.html

gce_net - create/destroy GCE networks and firewall rules

New in version 1.5.

https://docs.ansible.com/ansible/2.3/gce_img_module.html

gce_img - utilize GCE image resources.

New in version 1.9.

https://docs.ansible.com/ansible/2.3/gcdns_record_module.html

gcdns_record - Creates or removes resource records in Google Cloud DNS.

New in version 2.2.

https://docs.ansible.com/ansible/2.3/gce_eip_module.html

gce_eip - Create or Destroy Global or Regional External IP addresses.

New in version 2.3.

All of them mention dependency on apache-libcloud. That is true up to Ansible v2.5:

https://docs.ansible.com/ansible/2.5/scenario_guides/guide_gce.html

Google Cloud Platform Guide.

The GCE modules all require the apache-libcloud module which you can install from pip.

Starting with Ansible v2.6 a new notice appears:

https://docs.ansible.com/ansible/2.6/scenario_guides/guide_gce.html

Google Cloud Platform Guide.

Ansible + Google have been working together on a set of auto-generated Ansible modules designed to consistently and comprehensively cover the entirety of the Google Cloud Platform.

The Google Cloud Platform (GCP) modules require both the requests and the google-auth libraries to be installed.

The GCP modules require both the requests and the google-auth libraries to be installed.

Old and new style modules can coexist:

While the community GCP modules are not going away, Google is investing effort into the new gcp_* modules. Google is committed to ensuring the Ansible community has a great experience with GCP and therefore recommends adopting these new modules if possible.

Still they encourage to migrate to GCE modules:

As of Ansible 2.8, we’re encouraging everyone to move from the gce module to the gcp_compute_instance module. The gcp_compute_instance module has better support for all of GCP’s features, fewer dependencies, more flexibility, and better supports GCP’s authentication systems.

https://docs.ansible.com/ansible/latest/scenario_guides/guide_gce.html

Latest "Google Cloud Platform Guide".

https://www.ansible.com/google-clouds-journey-to-ansible-collections

Google Cloud's Journey to Ansible Collections (contains video presentation).