Nintendo has announced Mario & Luigi: Bowser’s Inside Story + Bowser Jr.’s Journey for 3DS. It will launch in 2019.
Here is an overview of the game, via Nintendo:
In this Nintendo 3DS remake of a classic Mario & Luigi action RPG adventure, fans can replay (or play for the first time) Mario & Luigi: Bowser’s Inside Story, one of the most critically acclaimed games in the Mario & Luigi series. It features new graphics and a new mode that tells the behind-the-scenes story of Bowser Jr.
Watch the first footage below (from 2:47 to 3:43). View the first screenshots at the gallery.