[Trivial Psychic]

I'm not sure how legit this is, but I ran into it on Reddit.  It suggests that someone has created a port to run Descent:Freepsace and Freespace 2 on the PSVITA.

Check it out if you're interested:
https://fuhen.homebrew-contest.com/submissions/21/

[Novachen]

This one is actually based on the openPandora Port.

It is also working with the Playstation TV. As you can use DualShock 4 with that, you can also rebind some additional keys if you need to.
Gamepad will never be the prefered way to play FreeSpace with, but in a way it is working and playable.
But i have again control Nightmares from my Wing Commander III playthrough on PSOne, which is also playable on Vita/TV. 

Also supports mods and campaigns that are working with retail FS as well. So Freespace Port, Silent Threat: Reborn or even the original Inferno.