Well you can but if this is for something like a helmet or something else that is going to be used constantly or is outdoors, probably not a good idea.
With plastic, prep is EVERYTHING! First, wash it with dish soap and hot water. Then wipe it down with rubbing alcohol (the clear stuff not the green or colored stuff) vodka or gin would work ok for this. Alcohol gets the release oils and crud out of plastic better than anything else I have found. Tack it off with a tack cloth, then scuff with at least 600g (400g is better) sandpaper, tack it off again to get the sanding bits off, wipe it down again with the alcohol. Let dry. Now some people will start to throw paint on it at this point, I personally use an adhesion promoter. I use the SEM plastic adhesion promoter. I've tried the Bulldog but I didn't like the texture it left and it catches every bit of overspray in the room. After you've got the adpro on there, shoot your base coat or sealer depending on your color scheme. Then the artwork, then clear of your choice. I personally would suggest using either Wicked, Auto Air, e'tac or some other multisurface paint instead of createx. Createx is designed specifically for use on textiles.
If you find a good UV protective clear coat , it will slow down the fading process , I have my first mail box I painted with standard createx about 5 years ago under a high UV clear coat and the color is just now starting to fade.
But if you can find WICKED (made by Createx ) than you will not have to worry plus it sprays better then createx.