You already can. Use a control laptop. Shard made a mod to let you turn off the robots from the base game and the national guard base for storage as well. I’ve got roughly a hundred of them sitting in a closet in my base.
If you are talking about hacking them all at once, I don’t know if that would be reasonable. If I were a military robot designer I would not make it possible to reset their IFF systems from a central system. That is the kind of vulnerability which leads to catastrophic hacking attacks by the enemy. MAYBE it would be possible on a squad level, but not all of them at a base at once.