In the video towards the end the companions have assigned targets, but how you do that is not shown. As for issuing commands, unknown.
From what I understand, there will be some kind of tactics system a la Dragon Age, whereby you can set up Drack, say, to detonate a specific attack by Cora whenever she uses it, for example, but that's going to be an 'if/and/or/then' system (under the hood, at least) rather than it being you as commander telling them to do that in the heat of battle when reacting to the enemy.
The real-time squad commands seem to be limited to 'attack this target' or 'move to cover' or 'move to point' - all of which were handled by the d-pad (or keyboard) in previous games.
Someone noted that in the recent footage, at one point the enemy had icons over its head indicating the squad had been commanded to attack it, and the icons showed what they were going to be attacking with. These icons weren't present when the squad were attacking in other bits of the same video. So it may be that when you direct your squad to target x and you have previously set up perferred tactics, these icons will show up if those tactics are being used. Those icons are a good idea, giving you a chance to react to what comes next. But it seems if this is the case, rather than you being the commander issuing orders to your squad, you'll be the follower, reacting to what your squad do off their own back.
I'll try to find the tweet that confirmed no tactical pause (other than the weapon wheel) - and I'll post it when I do.
Edit: Here -