not to be mean, but is there any reason to play the PAL version over the NTSC-U version? wouldnt PAL just be 50ghz instead of 60? I believe on modern tvs and monitors it makes no actual difference...
The PAL version (though only the english one, not the German and French ones) has a better english translation, a few wonky parts or stuff that didn't make sense in the english NTSC version were fixed. As example the dialog in the Heraldry Forest during the Mars quest is much better now.
There is only one bad thing: "Gamgee" and "Sophia" were changed to "Jamjee" and "Suphia". The rest of the english translation however is better and improved over the NTSC version while staying true to its charme and of course being accurate to the japanese version. (the German and French versions however are direct 1:1 translations of the NTSC english version, so they suffer from the same wonkyness here and there)
Game mechanics were improved, for example you can now hold the X-Button to accelerate the Item Creation process. (halves the time for creating an item, essentially allows you to create double as many items during the Orchestra song)
Several bugs, crashes and some black screen freezes were fixed, though not all of them. (most notably, it can still happen in the Cave of Trials when exiting)
As these versions here are most likely to be played on an emulator, on Duckstation you can force NTSC mode for the PAL Star Ocean 2, which works perfectly and makes it the "ultimate" english version to play, as there is a significant "smoothness" different between 25 FPS and 30 FPS. (the game itself swaps between 60/50 FPS in the camp menu and field maps to 30/25 FPS on the world map and in battles)
All in all, play the PAL version and force it into NTSC mode for the best experience.
The japanese PSOne Books version is also based on the PAL version, both are version v1.2.