Automate group assignment to agents

Feature Request Summary: 

Have the ability to setup an automation based on agents and groups
Like:

if an agent is new = assign group X and group Y
or
if an agent is in the default group = assign group X and group Y

Description/Use Cases: 
My agents belong to multiple groups.

When a new agent arrives, this person is assigned to the default group.
But I would like each new agent to have also other specific groups assigned. And I would like it to be automated.

Business impact of limitation or missing feature:
This is important for our business as we are growing really fast, onboarding a lot of new people each week. It requires a manual intervention which is error-prone and time-consuming. 

Other necessary information or resources: