Technically, there was never a native, "third-person" Dead Space title built specifically for the PlayStation Portable. However, (originally a Wii title) was ported to other platforms, and the PSP homebrew community has long worked on ways to make the Dead Space universe playable on the handheld.
Utilizing modern compression like CHD format to save significant disk space without compromising game data or load times. dead space psp rom repack
If you are looking for an authentic Dead Space experience on a handheld, you have better options on other devices: Technically, there was never a native, "third-person" Dead