I mean i've always wondered if Wiccan could possibly be Scarlet Witches son and he and her share a lot of the same powers (only Wiccan is on a weaker level right know) Could he undo Mday if he actually trained and focused his  magic and his mutant powers to seriously try. 
What do you think

I've been wondering the same exact thing...

I think that would be too simple.  It was something epic that needs something equally ground breaking to fix.  It would be nice if he could, but I guess if it's too easy then Marvel wont do it.

Or if he can't undo it completely then couldn't he give some of the mutants back there powers.

In my opinion, I think he could one day.  But like everyone else was saying, I'm pretty sure it won't happen.  That would be too awesome.

So far, it is looking like either Hope will do it or X-Man at the end of Dark X-Men.

No he can't, not by himself anyway.
 
Scarlet Witch is only an Omega Level Mutant because of Cnthon's influence on her. He gave her more power than she originally was suppose to have. He also gave her in affinity for the magics since he himself is the source of dark magic on earth and an Elder God.
 
It would be cool to see him do it.\ though... he needs training because he inherited his powers from his mother, only his base level is higher than him moms was

I think he has the potential too, and so do the Avengers apparently. Or they think he has the potential to match is "mothers" power.

i think he could just not yet

I don't think so. Dr. Strange couldn't pull it off when he was Sorcerer Supreme and he has more magic experience than any one else. But with training, some years of experience and maybe a mystical kick start from someone who knows. But I am betting that the Scarlet Witch fixes it later.

Kinda. When you think about it. Its a cheap response, but almost every Marvel both can fix M-Day and also can't. Wolverine or Iron Fist has as much chance as Living Tribunal or Galactus. They (Marvel) seemed pretty insistent on creating this situation, your going to need a character that can break the uh 6th wall to fix this lol (or let Marvel just have any character fix it though the power of He-Man, um, I mean the plot)

I'd LOVE to undo M-Day and i wonder if he can bring to life the x-students who were depowered and then murdered... I love the New X-Men Academy X students and some of them didn't show their extreme potentiall... Damn Scarlet Witch...