There are some technical difficulties when installing Office 2016 acquired through a Volume Licensing program on the same device as Project/Visio Pro acquired through an Office 365 subscription – this site has a useful table showing the various incompatibilities that exist: http://bit.ly/1S7ywQ8.
However, new licensing rights introduced in the June 2016 Product Terms (see page 59) mean that Office 2016 users with a subscription for Project Pro for Office 365 or Visio Pro for Office 365 may install and use a single copy of Project Professional 2016 or Visio Professional 2016 software on the device on which Office 2016 is installed, thus solving the problem.