Z9 has been a test bed for many of the weapons now fitted to WZ10 and WZ19, China has learnt a great deal from Z9 helicopters and it makes integration of these systems on new attack helos much easier
guess we can wait for this type of radar to appear on WZ10 and WZ19 soon
Z-19 looks really tiny and payload is probably very small. This thing wouldn't be too effective, at least not much more than a multipurpose helicopter similar to black hawk, mounted with a gun on the side.
Considering it's based on Z9 it should be able to carry at least eight HJ8 or TY90, or with the additional pair of pylons compare with Z9 it may be able to carry an additional pair of rocket pods.