isnt there a new method to completely remove+unregister the command rather then override since the new update?
tho i dont recommend unregistering aliases by hand as you can often miss something and result in unintended behavior
Yes, it is possible. This GitHub issue should help you: https://github.com/pmmp/PocketMine-MP/issues/1229
Not exactly, that won't work. You have to pass an exact instance of the command you want to unregister, so you would have to get it first.