Depends on your definition of “accent” (yes, really). Is an accent a deviation from standard/dictionary, or is standard/dictionary also an accent?
Assuming standard isn’t accent, depends on the zone/individual. We all know about Brooklyn and Southern drawl and Minnesotan, etc.
Assuming standard isn’t accent, Americans have less accent than other English-speakers, but more accent than you’d think. For example, Americans say “budder” instead of “butter”.
It’s not an accent. We’re the only people in the world without an accent. In fact, I’m the only person in the world without an accent.
Americans are the ones without accents.
If you didn’t almost certainly have a gun on you right now, you’d be in for it mister.