The "highly compressed" files you see online are typically modified versions of for the PSP. Understanding "Tekken 7 PSP" Mods

The PlayStation Portable (PSP) is a handheld game console developed and published by Sony Computer Entertainment. Released in 2005, the PSP was designed to compete with other portable gaming consoles, such as the Nintendo DS. The PSP offered a range of innovative features, including a widescreen display, stereo speakers, and a UMD drive for playing games and watching movies. Although the PSP is no longer supported by Sony, it remains a beloved console among retro gaming enthusiasts.

These mods use the Tekken 6 engine as a base and update various assets to mimic the Tekken 7 experience on handheld devices via the PPSSPP emulator.