I am trying to create a World of Warcraft addon which allows a player to move towards the side of a player. Just like the follow function but instead of walking behind the player at his side. I was thinking on getting the player's location with UnitPosition and make the player walk towards that location by adding:
math.cos(direction player is facing in radians)*(length)
math.sin(direction player is facing in radians)*(length)
This is not possible today using Blizzard's current API.
Player movement addons were possible during the early days of Vanilla. People made auto-run GPS-style addons to help characters auto-travel on foot from one town to another.