I'm leading a real-time animation project to launch a 24/7 live tech TV news channel streamed thru twitch/youtube... all virtual: characters, scenarios, cameras, synthesized voices, lipsync...
Where can I find people that could be interested on it?
How to invite them?
Which social channel?
It's possible you're confusing a co-founder with a technical resource. Your first employee, someone with technical skills you don't have, or just someone you can't pay with cash, is not a co-founder. A co-founder is someone who shares your vision for what you hope to achieve, and who is driven to accomplish the same goals because it's personally important to them.
Not being able to pay a first employee doesn't make them a co-founder. It simply means you need to figure out how to compensate them for their time, which may delay the start of your project.
And this is a project, not a business (yet), so definitely not a co-founder, though perhaps a collaborator.
Attracting anyone is partly being able to express your ideas, but also importantly being able demonstrate that you have done the work to reduce most of the possible risks of being involved in the effort.
If it's a passion project with no way to make money, it's even harder to get someone to share the work of your hobby.
My recommendation is to work on defining the rewards of your enterprise, as well as taking the steps to eliminate or reduce as many risks as possible impeding you from reaching your goals. People invest their time, energy, and money in good plans, not good ideas. You will stand out from others if you have a solid plan, but not if you're only hawking an idea.
Luckily your technical requirements are very specific. I would start by going to one of the contract programming job shop sites, and hire people and see how you like them. If someone seems exceptionally good, make them an offer. You will never know from a resume if they know what they are doing. The people who program well are often poor at writing, and the clever frauds who know how to polish a resume to the point where it dazzles you are not what you are looking for. Expect to go through half a dozen people until you find a winner. Then run with them. Good programmers are hard to find, but many programmers enjoy Unreal Engine work, because that is the gaming biz, and it has a lot of riches and is very challenging. Real time animation is incredibly challenging, but people love it, and a successful product in this area can be quite valuable.