While Scribblenaughts Wii U version is getting Mario and Zelda series characters, it turns out the reason they got left out for the 3DS version was due to timing. 3DS version was finished before the Wii U version and the idea for those characters occurred during the period the carts were being mass produced for the game.
http://www.egmnow.com/articles/news/...to-bad-timing/
Capcom announces Ace Attorney 5 for the 3DS will be the first game in the series to feature voice acting although it will lose the series special sound effects as a trade-off.
http://www.egmnow.com/articles/news/...-voice-acting/