Movement sensor for vellbus

are there any movement sensors that can be connected directly to the vellbus,
or is there another way to connect them?

You can connect a sensor (dry contact normal open or normal closed) using the VMB6IN module.

For me, the question is more like “is there a movement detector without 230v power but 12-18v DC” ?

For inside use you can check here:
velleman.eu/distributor/prod … ?id=374758

We do not have a dry contact model for outside, then you will have to open the detector and bring out the relay contacts.