The bottom side of the Moto G (2nd Gen) features a microUSB port but unlike its first generation, there is no microphone on the bottom as a primary microphone is hidden under the second loudspeaker grill on the front. (techone3.in)
It has USB Type - C port, 3.5 mm Audio Jack and loudspeaker grills at the bottom. (techandroids.com)
It is worth noting here that there is just a mono speaker available under one loudspeaker grill while the other one has a microphone to capture audio. (techone3.in)