I think you can easily spray paint the door opening sensor as it relies on magnet ,the motion sensor’s plastic body can also be spray painted as far as you don’t spray the sensor window.
I think for door sensors it should be no problem as mentioned before.
For Temperature they sometimes have holes to let air in, this hole shouldn’t be sprayed shut. Also I don’t know if the sensor likes direct contact with spray paint.
Sounds like a good idea!
I have talked to Aqara about the u200 lock, when my door is white and silver on the inside and black on the outside, but they said that it was not possible with the lock to have different colours. Sensors should not be that hard to make in different colours