There has to be a reason why everyone in the Watchmen universe was saying he is a god.
Yeah; because he was the ONLY one with any actual super-powers. Hell, even in DC where it isn't difficult to find someone who easily exceeds his power, Superman often gets referred to as a "god". It's meaningless so far as it goes. "God" is usually applied as shorthand for someone who's power radically exceeds their peers. In Manhattan's case, regular human-beings.
Things like capability of creating life(not clarified to what extent or period of time) aren't anything that can be used in a fight, and being apart of divergent time-lines are in no way applicable to a fight.
Everyone's entitled to their opinions, but there is literally NOTHING in Manhattan's corner to suggest he wouldn't get absolutely dismantled.
Even off of hyperbolic statements, Sentry hands him his ass, as he's been referred to as omnipotent.
So, feats or statements, Manhattan can't compete in the slightest.