Change from OpenGL to Vulkan (Vulkan handles 3D rendering much faster on modern Android devices).

Go to Settings > Graphics and switch the Backend from Vulkan to OpenGL, or vice versa. Ensure "Buffered rendering" is turned on.

God of War 2 Highly Compressed for Android: PPSSPP vs. PS2 Emulation Guide

It is a fan-converted “demake” that plays like God of War 2 but runs on the PPSSPP engine. The storyline, levels, and combat system are identical to PS2 version.