I would recommend Firstly starting with a Game Template from the Marketplace that has most of the basic features you desire. Secondly, seek developers to join your project to build the unique features. Thirdly, reverse engineer the template and learn unrealengine in the process. That’s what I’m doing with ExORION Survivor. From my experience it has been really tough to grab the attention of fellow developers with concepts that are too radical. Thus I’ve been developing my game concept solo.