Thank you!
I found something very interesting, someone created a decoder for this particular type of weather station:
https://github.com/merbanan/rtl_433/blob/f775d1ac6c672cd0d1251600e2aaa8cfefda6c46/src/devices/fineoffset_wh1080.c
It seems to be usig Frequency-Shift-Keying (FSK) encoding over 868.3MHz.
Does RFLink support FSK encoding?
I wonder if it is also possible to connect a generic RTL-SDR usb dongle to home assistant.
I found this post:
https://community.home-assistant.io/t/home-assistant-add-on-amr2mqtt/378196