It doesn’t really need ‘confirming’, it’s just that PAL consoles ran slower than NTSC ones. Some games were ‘fixed’ for PAL, so there was no slowdown running on the slower hardware, but they’re the exception rather than the rule.
The emulators will generally emulate this hardware difference since forcing alternate timings can cause no end of problems in some games (though you can force different behaviour in some emulators), but it’s just as handy to use NTSC rom images.
For most console games you will get a difference in speed across regions, though you’d really need to specify the emulator, game, game rom region and emulator region config used before I could really say specifically what you could expect to see.