Z-wave light switch w/ motion and dimmer?

Are you in the US or the UK?

There are many light switches that can work with the smartthings hub in the US, both the BNZ wave. But none as yet that also include a motion sensor, so you need to use a separate sensor for that.

If you are in The UK, there are no switch options on the official works with smart things list, but there are some that you can try. See the FAQ in the UK section.