Help you find to Optpix for current game engines

As the industry transitioned to the PlayStation 3 and Xbox 360, hardware memory expanded into hundreds of megabytes, and the critical need for rigid 4-bit and 8-bit color palettization faded.

Full text of "AIO Project: PS2 v2.0.1 (2021)" - Internet Archive

A single uncompressed 512x512 texture in 24-bit color takes up 768 KB of space.

The PS2 handled transparency (alpha blending) in unique ways. Optpix Image Studio gave artists granular control over the alpha channel during the color reduction process. Developers could precisely map out which pixels were completely transparent, semi-transparent, or opaque while simultaneously locking down the color palette. 4. Direct TIM2 Customization