The game is supposed to run at 60FPS (fixed framerate). Looks like your machine can't handle the game performance-wise. A rare players had issues with performance on their machines, but most certainly because of aged hardware. Recommended setup is Win-10 x64, Intel Core i7, 3.6GHz, 16Gb RAM, NVidia GeForce GTX 1060. However, some players may tell about "slow combat" because they want all moves to be x2 times faster. Moves in Fighting Games are supposed to be fast, but slow enough to be reactable and punishable. This is a gameplay basis.
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I think it's probably my machine. I played on an HP Laptop, Win 10, 12 GB ram, AMD Ryzen 3, AMD Radeon Graphics. The game moved Sluggish even though the startup video brandings, which lead me to believe it can be some sort of isolated incident. I admit the gameplay seemed fun but I had a terrible experience.