A recent interview published by 4Gamer with Mr. Yosuke Hayashi, Producer of Hyrule Warriors, gave some insight into the Nintendo 3DS version, called Hyrule Warriors Legends. The super popular Amiibo line will be supported in the game, just like it was in the Wii U version, though any changes or additions are yet to be revealed. New characters were also teased though no firm date for their later announcement was given either. Hayashi did confirm that Tetra, Toon Link, and King of Hyrule DLC for the Wii U version will be included in the box as a code, in case you wanna share them with someone else who has a Wii U.
The main feature of the Nintendo 3DS, the stereoscopic 3D, will only be usable on the New Nintendo 3DS hardware, as Hyrule Warriors Legends pushes the console to its limits. Legends will also be a Game of the Year edition of sorts, including all previously released DLC for the Wii U version of Hyrule Warriors. Currently there are no plans for DLC for the Legends version, though if demand proves high they might add onto it. Lastly there will be no Challenge Mode (beat a challenge and gain tons of Rupees) due to the smaller screen size. A lot of the work on Legends was to optimise the handhelds hardware so the spirit of the game, taking on large amounts of enemies, would be kept intact. If all goes according to plan, Hyrule Warriors Legends will release in the first half of 2016 for North America and Europe, along with the release date of January 21, 2016 for Japan.