Can spray paint made for plastic surfaces work on metal surfaces?

Absolutely. Paint made for plastic surface is more flexible after it dries, hence it won't crack. Metal surfaces don't have the problem of flexing, so plastic paint will work fine. Note that plastic paints tend to cost a bit more because there are polymers which allows a bit of elasticity is present.Can spray paint made for plastic surfaces work on metal surfaces?
The spray paints made for plastic tend to be for multi-surfaces so probably. Best way is to read the fine print on the can. If it doesn't say it will work on metal then you don't want to use it.