I don't have any prior knowledge about Edward Elric but I feel like because of his higher attack potency, lifting strength, and outstanding intelligence, he should be able to overwhelm Gumball in a fight without much difficulty. Although Gumball often runs away to think of a better way to win, those are in situations where he doesn't think his position is currently advantageous. He clearly underestimated Edward and he isn't too fond of strangers insulting his head's size, so I think that at first he will try to directly confront the opponent. Gumball's regeneration should help him survive, but the default battle conditions make it so that Gumball doesn't need to die to lose, he just needs to be beaten and tired to lose, so his regeneration won't help him forever, especially since it states on Edward's profile that he doesn't like killing, so Gumball won't be losing via death. I don't know if there is a reliable way to determine at what point Gumball would end up using his hax, so since he doesn't typically use them, I'm going to consider it unlikely to come into play in this matchup. In any case, I see an interesting Alchemy ability listed on Edward's profile that allows him to manipulate matter and energy, so he's got his own hax, which are probably more likely for him to use than Gumball considering it seems to be a prominent aspect of the series he's from.
I vote for Edward, but although I think this battle isn't unfair, I'm not sure if other people will approve of Gumball's loss count increasing every time he's part of a versus thread. I am very unbiased so I don't mind the big and increasing loss count, but I'm sure there are other people who are finding it annoying and/or suspicious. You might want to take this into consideration.
