There is a retroarch cia for the ps1 afaik, but i doubt it can run smoothly rn. It is worth trying though (if i knew of a way to get reliable rips of my own games, I would try it myself, but i dont trust anything in my laptop drives rn)
PCSX-ReARMed has a chance of running well on the n3DS, but I'm not sure if it will ever be full speed. The 3DS only has ARMv6 which is a lot slower than ARMv7 (every modern Android device uses ARMv7)
The OpenPandora ran PCSX-ReARMed very well at 600mhz but that was an ARMv7 device as well.
It seems possible to run PSX games at good speed on the n3DS, but it depends on how good they are at optimizing.