This is a grey area. Datel (the manufacturer) no longer produces or supports Action Replay for PS2. The copyright on the software technically remains.
Most websites offering "Action Replay PS2 Europe ISO" are not preservationists. They are ad-heavy, malware-ridden forums. Downloading a random ISO from the internet is a fast way to get a virus on your PC or a corrupted .bin/.cue file that bricks your emulator configuration. action replay ps2 europe iso
The most popular reason. The allows PC gamers to play PS2 games in 4K resolution. However, entering cheat codes via raw hex editing in PCSX2 is complex. Many users prefer to boot an Action Replay ISO within the emulator first, select cheats, then have the emulator "swap" to the game ISO. This replicates the original hardware experience. This is a grey area
If you are using the PCSX2 emulator, It is a waste of CPU cycles. Instead: Most websites offering "Action Replay PS2 Europe ISO"