The developers considered making Bowser a playable character early on in the planning but scrapped the idea to keep the focus on Mario and Luigi.

Touching Luigi's cap on the title screen will allow the player to mess around with his mustache, nose, and cap, as they would during game play. Each action made to Luigi will alter the top screen.

A frame of Bowser Jr. slamming his hammer is graphically faulty.

Within the game's data are sprites for the Ice Flower, Yoo Who Cannon, and Jump Helmet attacks from Mario & Luigi: Partners in Time and Mario & Luigi: Bowsers Inside Story, indicating that these moves were planned to make a return.

Of these three, the Jump Helmet is the most complete, with the sprites being reworked to use the 3D perspective mechanic introduced in Dream Team. The Ice Flower's assets consist almost entirely of copies of preexisting sprites, with the flower itself being the only unique graphic, and while the Yoo Who Cannon features bespoke visuals for Mario & Luigi, the cannons themselves are mostly identical to their Bowser's Inside Story sprites.

In the UK and Australia, Mario & Luigi: Dream Team and Paper Jam both had "Bros." added to their subtitles with no official reason given for either. However, it is possible that this was done to avoid any legal issues with UK trademarks for the original subtitles that were still valid at the time of the games' releases. The trademark for the name "Dream Team" was filed in the UK in 2010, and there were two trademarks for "PaperJam" as well as a brand of toys that were sold in the UK under the name "Paper Jamz".