Patronum gives you the ability to provision and de-provision Google Groups for your users automatically.

Group Provisioning

To automatically add users to a Google Group simply select the ADD but and PROVISION users into a group.
Select which group you want to add your users to, and define the default permission users will obtain when added to the group.

Deprovisioning of Groups

When removing users from your  Google Workspace environment you can use the deprovisioning option. Deprovisioning options are available by selecting the deprovisioning button.

It is not possible to have both provisioning and deprovisioning tasks within the same policy.
With the Google Group deprovisioning policy you can perform the following tasks:-

Transfer group ownership to executor

This option allows you to transfer any Google Groups which users are currently managing to a designated alternative known as an executor
The executor can be set for the whole policy or specifically for Google Groups. For example, you may want Files transferred to a backup account but want Google Group management to be the responsibility of the departing users’ manager or system administrator.

Remove user from Google Groups

Within the policy, you can remove departing users from all Google Groups. This is useful if you have previously granted Google Groups access to Files and Folders or Calendar events. Removing users from Google Groups will automatically remove them from all group events and revoke file access.

Override policy executor

As previously stated above, within the policy, you can also override which executor account will become the manager of any Google Groups.
Simply enter the new name or email address of the new executor account.