Tekken 6 [BLES00635]

Because RPCS3 generated inaccurate savedata when you booted the game most likely

So, how do you fix that?

Go to the Downloads page, browse the Complete Build Catalog, find and download Build# 4970. Unzip that somewhere else, ensure pad is setup as well as any files you need to boot games, then start the game. It'll likely go partway in and lockup. Reboot again, and keep doing so until you can get through to the main menu.

At this stage, exit the emulator. Go to your dev_hdd0\home\00000001\savedata folder. Copy the folder BLES000635 and drop it in the same place (deleting any such folder if it already exists) in your current emulator build. It will now detect that savedata and complete the boot.