I got the Philips Hue bridge and can in both the Hue and the Essentials app see my Hue Dimmer remote and the Motion Detector. When I link diyhue with my Hue Bridge all my lights are imported - but not the dimmer remote or the motion detector.
What is the trick to get those to show up in the apps?
I assume you have 1 generic bridge and diyhue - no other hardware.
In short: the original Bridge does not expose sensors and switches.
If you want to use Zigbee Sensors and Switches we suggest you use either Deconz with Conbee 2 dongle or Zigbee2Mqtt with a Dongle that is supported by them.
This means: you need extra hardware and software to achieve your idea.