I will also search for "Mortal Kombat Shaolin Monks PSP download safe" to find any relevant discussions. results are about guides, not game downloads. This confirms the confusion between guides and game ROMs.

These handheld devices easily run the game at full speed, allowing you to upscale the resolution to 1080p or higher, apply widescreen hacks, and map controls natively to modern dual-analog setups. 2. Android Handhelds and Smartphones

Hold L2 and press Square, Up, L1, R1, Left, Right, Square .

While you cannot play it natively on a PSP, you can play the original PS2 version on modern handheld devices using emulation: