I live in Turkey. We use the PAL standard here. All our games and PS4s are PAL. But recently I found a seller who sells NTSC games for lower prices. I know it will work on my PS4 but is there a disadvantage to using an NTSC game on a PAL PS4?
No PS4 console or PS4 game is in PAL (or in NTSC for that matter). What they produce on the HDMI output depends on what the console negotiates with the monitor/screen connected to it. Most of the time this will be 1920x1080@60Hz. This “Full HD” resolution is one of the most common resolutions sent over HDMI and practically supported by any screen/monitor. (A game might request a lower resolution to be driven by the console, or the console itself will drive a lower resolution if the screen can’t handle 1920x1080@60Hz, but this is rare. – And it will still work anyway.)
You can search online for cover photos (front and back) with “game name ps4 cover ntsc” or “pal” and will find out that not a single cover mentions PAL or NTSC.
Independent of video resolution and standards: the PS4 does not employ a “region lock”, so all games work in all consoles.
If someone uses the words NTSC or PAL with PS4, I guess it is to indicate the market the product was intended for, not a technical detail.
So, is there a disadvantage? Yeah, the price might be. ;-) Language and subtitle options might differ. Age restrictions/labels will cater to the intended markets only. And there might be some DLC availability/compatibility issues if you shop with a Playstation account linked to one market for a disc bought in another market.
I remember double checking the compatible disc IDs in some DLC description before buying.