What do you mean by 'outside the platform'? Please specify. Can I invite any existing freelancer at upwork to join my team if I like his/her profile. How to contact with them or send them message. If I click on contact button then it goes to my homepage. Really confusing system!
As an agency owner, you can add members to your team and manage bidding, interviews and payment processes, while your agency contractors focus on completing the work for the clients.
Please check this help article for more information on how to add team members to your agency.
Let us know if you need any further assistance.