Newer SMB2 probably wont happen since they canceled Newer SMBU and stated that Newer Plus would be their final project.

Playing a newer team game on a 3DS Would be awesome! ⇨ you can play Newer DS on 3DS :P

As a follow-up to my old reply, they said they will never make Newer 2. however a group of other hackers are making Super Mario Bros. Next, which has around the same quality level. For now only an edition with cut levels and season minihacks are available.