I am not sure how it works, but sometimes I can see them when I am in combat when I played on the PC version. I would pause the game and then click on an enemy group. Then on the left side, would click on a ship. Can't remember if a small magnifying glass was there or not. Been a while since I played on PC so when I tried it on console I couldn't see them. I think we need to research some tech to be able to see the other ships or maybe their level is higher than our tech level and can't see it.
Again, don't remember how it exactly works so I think I got some things wrong.
How far in tech are you?