I don’t see this effect as my heat pump is situated on the north end of the house so never gets any sunshine. The temperature from the manufacturer’s sensor seems to match that from the local weather station reasonably well, except during a defrost.
While looking into getting a heat pump, I did wonder if installing it in a sunny location would be beneficial, but I could not find any sources that supported that idea. In fact, I only really found warnings about the detrimental effect sunlight could have on some of the components, shortening their lifespan. [citation needed]