If I can suggest something, it would be that Defiance ONLY considers the skirmish itself when assessing morale and so on.
While teleporting out is a strategic advantage, it still leaves the other guy at an advantage for a few minutes or hours at the original skirmish site.
Vobians who leave the table aren't dead, they're not even cowards. They've just withdrawn because it seemed prudent.
Defiance abstracts broken troops out of the fight if they don't rally. Just set up individual and unit morale to provide the appropriate actions for troopers who are requesting a teleported evac.
SO, teleported escapes would be the racial / cultural / species Unit Morale Failure. On a morale fail the unit would do whatever they need to to prep for teleport-out. If they don't rally in the next resolution they have teleported out. So, if prep allows them to take cover, use Regroup, if it requires them to stand still use Communications Breakdown. If individuals are likely to take cover when threatened, use Cower, if they are confident of getting teleported out by their superiors then use Cool Head.
This is part of your answer. It works fine for teleporting troops out if the going gets tough, but if you want to be able to teleport them back in at will, I'd say... well, forget it, or just use it for scenarios and don't try to directly cost it. Facing an army where troops could teleport out and then back in I'd want 2-1 odds in my favour.
Now, using teleportation as your means of moving instead of walk, sprint, jump or fly, might be reasonably reflected by Phase Walking which is rumoured to have been costed but hasn't been published. I can't help with that! Getting to teleport a single squad into position per game might be a more expensive and versatile version of Reserves, ie., it's a Strategic Advantage. Using teleport to set-up attacks or defence is a strategic level ability and could be reflected by scenario choice (eg., it's Advance to Contact but we're teleporting troops to the front line).