It seems like Sonic Lost World will adopt a similar multiplayer approach similar to Super Mario 3D World, eschewing online mulitplayer in favor of keeping the competition to your friends in the same room.
“We’ll have different multiplayer modes on both Wii U and 3DS. On the Wii U, there’s booth cooperative and versus multiplayer.” said Takashi Iizuka, the game’s producer. He continued:
“In cooperative play, Sonic will be using the Wii U GamePad and someone can be supporting Sonic in co-op with the Wii Remote. In versus mode, one player will be playing on the TV screen and the other player will be racing using the GamePad so you don’t have to have split screen. You both have your own screen and can race each other. The Wii U multiplayer is not on the Internet. It’s basically everyone sitting on the same couch. The 3DS for the first time we’re having 4-player versus racing over Wi-Fi and the Internet.”
To sum it up, the Wii U version will have both cooperative and competitive modes, with the co-op sounding similar in theory to Super Mario Galaxy; one person playing the main game with others using Wii Remotes to support the action. The 3DS version, on the other hand, will focus on four person, competitive racing whether it be local or online. Historically this goes against the grain when compared against the rest of the industry, but Nintendo has always excelled at local multiplayer so it could just be that more now developers are realizing the Wii U’s features really add a great deal to this tradition.
Source: My Nintendo News