Pretty sure you'd probably get knocked out. Fighting on skates is hard enough, if you've never done it you really have no idea.
Generating force is hard, balancing while chucking, and tussling for leverage and position is hard. It already takes a tonne of effort to fight.
trying a spin would just open you up for the other guy. It's not the same as if you are standing on the ground, or a mat.
While it is not as easy as on your feet, you have have any sort of balance it isn;t thst hard. I grew up as a fighter in hockey, never had an issue. The hardest part is wrestling, throwing punches is easy.
But I agree, if you tried one, you would probably be knocked out before it landed. If you did land, I predict broken hand and a knock out if you connected. You can get a ton of speed going if you know how to spin.