If you want to ask about J-20's versatility that's fine, but the topic itself is so done to death that it's no longer humorous, it's just a bloody waste of time. I'm going to delete your question and everyone else's response including my own -- if you want to ask about J-20's versatility then don't try to be cute, just ask it genuinely please.
No, the strike role for a fighter sized aircraft can be done with a single pilot, you don't need a second pilot for that. Even for bombers, arguably the need for a second copilot isn't as vital as it once was.
The twin seater J-20's role will likely be for enhanced battle management/control purposes, and its weapons bay is almost certainly the same dimensions as the single seater so it's not like it has a greater weapons capacity.
