画面真好，3D很好，特别是开凸出效果。赞赞赞！感觉是移植街机的？

我也看到过街机，难道是家用机改的？

找到了，确实有街机版，家用机移植的。wiki：
An arcade version of Streets of Rage 2 was released onto Sega's Mega Drive based Mega-Play hardware. It uses a regular credit system. In this version, all 1-ups have been replaced by money bags, there is no in-game timer and the difficulty levels are one step above the Mega Drive version. Scoring is kept by number of KOs, instead of damage inflicted.