NAV2 (.nav2) is a navigation file associated with NPC “navmesh” map navigation. These filetypes are specifically present in Metal Gear Solid V: Ground Zeroes (2014), Metal Gear Solid V: The Phantom Pain (2015), and Metal Gear Survive (2018). Tools for editing NAV2 are available.

https://github.com/oldbanana12/Nav2/wiki/Editing-Flags

https://www.bountysource.com/issues/91675424-navnavigationfile-nav2-format-1013-00-submission-pending