If you're just looking to play Tekken on PPSSPP:
Most versions require at least 2GB to 3GB of storage space after extraction, despite being "highly compressed" in ZIP format. Installation Guide (General Mod Process)
: If you want a native PSP fighting experience, Tekken: Dark Resurrection is widely considered the best complete game for the platform. Tekken 8 On Android : PPSSPP How to Install & Run Offliine
: Place the TEXTURES and SAVEDATA folders into the PSP directory on your device storage.