This module is self-explanatory; it is used to manage the power stage of your VM. The following example power cycles a VM:

- name: Powercycle a vm
  vmware_guest_powerstate:
    hostname: "{{ vsphere_host }}"
    username: "{{ vsphere_username }}"
    password: "{{ vsphere_password }}"
    validate_certs: "no"
    folder: "/vms"
    name: "yet_another_example_vm"
    state: "reboot-guest"
  delegate_to: localhost

You can also schedule changes to the power state. The following example powers down the VM at 9 a.m. on the 1st April 2019:

- name: April fools
  vmware_guest_powerstate:
    hostname: "{{ vsphere_host }}"
    username: "{{ vsphere_username }}"
    password: "{{ vsphere_password }}"
    validate_certs: "no"
    folder: "/vms"
    name: "yet_another_example_vm"
    state: "powered-off"
    scheduled_at: "01/04/2019 09:00"
  delegate_to: localhost

Not that I would ever do something like that!