The charge unit trait states a different effect that it actually gives.

It states "Charge +3 moves and initiative on the first turn of combat"

but alas it gives +3 moves and +3 attack damage.
You can see the difference between a unit with charge in combat on the first turn, before and after move here, sorry for the without charge bonus is defending and adds +5 defense, im fighting a lone wolf and killing it would make it slightly harder to make the screenshots .

Here is the one with charge bonus, 3 units of spearguys. 2+3 moves, 7+3 (2 from traits, 1 from trog) and +3 from charge, times 3 gives 39.

Now I will show one that moved 1 square, (which is defending), notice the 2 moves, and minus 9 to attack, also no change to initiative.

Sincerely
~ Kongdej