The choice of Chris Pratt to voice a character who usually has a heavy Italian accent, when he speaks at all, is an obviously unusual choice. It’s just not the sort of voice one expects from Pratt. On the flip side, one could imagine say, Danny DeVito voicing the Italian plumber from Brooklyn, with DeVito himself being an actor of Italian decent from New Jersey. And while the movie will be animated, and so the actor’s look is hardly important, DeVito could clearly play Mario in a live-action movie, which makes him feel even more right for the role.
Source: Source: Cinema Blend