Handling a new device that is almost the same as an existing one

[jpmv27]

I recently purchased this device from AliExpress. It's not identified with a Make or Model, but seems to be the same as this ORIA WA50 on Amazon.

The sensors are decoded with protocol 47 and recognized as "Conrad-S3318P".

In fact, there are a few differences between my sensors and what is decoded:

• my sensors only report temperature, not humidity (humidity is reported as 0)
• my sensors do not have a button
• the base and sensors do not support a channel selection; sensor 1 reports channel "2" and sensor 2 reports channel "3"

I will probably just live with this, but I was wondering how such a situation could be handled if I wanted to add a custom decoder for these sensors.