In the closed Beta you could cancel the charge like the Charge Abilities in V2, now you cant at all.
I havent read anywhere that it was changed to not be cancleable.
This makes the charge unintentionally a really bad ability as you most likely fling yourself off the map if used near cliffs or that you charge too far into the enemy, leading to a swift death.
And you also cant use your charge to stagger a pack of maulers or Ragers in front of you, you charge right a few meters past them.
Edit: After some more playing, it is possible to cancel it, but for some reason you have to spam block or S to make it stop. And I also found out that you cant cancle the charge for the first second you are running. (Is this 1 second of “cant cancle” intended?)