i know bc wheels are made out of like a front bicycle wheel that coasts but is there a way to make one out of a unicycle wheel? i know it sounds retarted but i was just thinking about it
You would need a different Hub (hub of a front bicycle wheel)
and then just get the plates to stand on and you are good.
If you got plates that attached to the bearings on a unicycle wheel then yes.
The plates would then move independently of each other, I wonder how that would affect the handling. also, I think that you would ruin the bearing pretty fast with all of your weight hanging off of the edge of it.
So basically you’re better off with a bike wheel 
Correct, unless you put some creative thinking to use and figured out a real solution. In the long run though it would certainly be easier to just use a bike hub.
and a lot cheaper… i don’t know why uni wheels have to cost so much…
because they’re produced in relatively small numbers and so have poor economies of scale