Patch 5.0 notes mention them and they are even showed on the anniversary trailer but i can't manage to find them, only thing i know is that they are supposed to be located on Triggers
StarCraft II now supports formation movement, which can be turned on/off for each player via triggers.
Unit can move and attack in a square formation with predefined separation distance between them.
Currently, this formation movement won’t force all units in formation to maintain the same movement speed, which is different from the War3 version.
Modders can tweak this data to customize the behavior.
The only thing i have found on Triggers so far are these two section about UnitPathabletoUnit/Point, i am pretty sure that's not what i am looking for but that's as far as i can go for now... Did anyone found the magical WC3 Formations location? If so i would love to know it aswell, thanks in advance for the eventual help