I see. Sorry about the misunderstanding. :/ But I'd kill for another Retro developed Metroid game. I recently replayed the original Prime game, and I'd honestly forgotten what a masterpiece it is. Oh, and I didn't hate Other M either. The story was disappointing but aside from that, a fun enough outing.
Back on the topic of Shulk, though, I think the biggest obstacle to his entry, currently, is the abundance of sword-wielders in Sm4sh. I myself am not complaining about this, I love sword wielders, and the Monado is unique. But I feel as though it's an excuse the developers could use (or have used, by this point) to not include him.