Death Battle wise, Shantae wins. She has a lot going for her in terms of speed, strength, arsenal, and combat experience.
1 Minute Melee wise, I can see them giving Shovel Knight the win. To me, I feel popularity is what gives the character the win, no matter what. Look at Sonic Vs Flash for example. While Sonic runs faster than the speed of sound, Flash runs faster than the speed of light. And yet, Sonic won. Then again, there are certain battles that give the other character the win because of their loss in a Death Battle. And then again, Scorpion is more popular than Ghost Rider, yet Ghost Rider won. But I don't know.
Though I didn't expect us talking about Death Battle, because I'm actually a fan of the series