Great!! The swap trick works with PSONE !!
 

Hi ! The swap trick works with Psone and you can play imported games without the boot cd!
I used a PAL PSone with mod chip, and when the speed from 2x, go down to 1x (during the black screen with scee logo) you can swap the disk and put your NTSC game. It will safely boot. When the game is loaded you can also close the top panel of the psone.