please provide me a configuration that will support the 'Request Invitation' process

Install module "Invitations" and make sure that the following option is on:

Studio > Invitations > Enable registration by invitation only

You can send join links to invitation requests from Account Dash > Manage > Requests

Then for invitations mode I would suggest to enable auto-activations for Accounts and Profiles:

Studio > Settings > Account > Automatic account activation after creation

Studio > Persons|Orgs > Activate all persons after creation automatically

change 'manage' to 'moderate' (more descriptive)

It's not only for moderators and moderation process, it's for admins to manage content in bulk as well.