He'll just have to do his stealthing somewhere else.
Metal Gear creator Hideo Kojima doesn't believe Solid Snake will return as a playable character in either of the upcoming Super Smash Bros. games this year.
In an interview with Geoff Keighley for Twitch, Kojima stated, "I'm not working on that game so I don't know, but I don't think that's likely."
Kojima, however, is not against the idea of the stealth icon returning to the fray. "Well, if Mr. Sakurai is watching this, please use Snake" he added.
Super Smash Bros. for Wii U and 3DS are currently scheduled for release this year.