Dragon Ball Fighterz characters run at lower frame rates. Character animations run at 8 fps, 10 fps, 12 fps. It creates the Anime look and motion, and it looks really cool. Guilty Gear runs the same way. It depends on game whether higher frame rates are better or not. Sometimes higher is better, sometimes its not. It depends on game. I like higher frame rates in Fighting games like Soul Caliber and Street Fighter. But I prefer in the lower frame rates in the 2D or 2D/3D anime style fighters like Guilty Gear and Dragon Ball Fighterz. It really depends on game and different frame rates can be used as a stylistic choice.
Heres a Digital Foundry video on Dragon Ball Fighterz frame rates.