How to pair Legrand (Netatmo) devices via ZHA?

I have a Sonoff Zigbee 3.0 Dongle P and I would like to use it with my Legrand devices (mostly blinds) that have Netatmo controllers. I really would like to use my dongle instead of the official Legrand gateway.

Canbyou tell me how to do it? Is it even possible? I tried once some months ago and I was able to see a device, but it disappeared right after setting it up.

Thanks A LOT.