While most modern emulators like DuckStation or ePSXe have built-in "cheat" menus, many enthusiasts still seek out the original GameShark ROMs for several reasons:
Almost. GameShark was the North American brand, while Action Replay dominated Europe. The underlying code structure is identical (8-digit hexadecimal with 3 or 8 prefixes). You can use Action Replay codes in a GameShark emulator plugin and vice versa.
: Open your emulator and "boot" the GameShark disc image first.