The smartplug (HS110) doesn’t block or otherwise interfere with the overall load that Sense is “seeing” at your mains other than add about 1.5W overall … think of it as Sense-native detection being unaware of the fact that a device is plugged in to the smartplug … because it is unaware! This is actually handy because you can compare the smartplug “ground truth” data vs. Sense-native detection.
You can tell Sense in the smartplug-detected Settings > Manage > “What’s plugged into this?” and then specify the Sense-native-Detected device.
See here for more details: