Not possible in the sitemap based UIs. There is a fairly comprehensive set of widgets, but no means to make custom widgets.
The HABpanel UI allows extensive custom widgets.
In the sitemap usage, you can of course use icons to reflect the state (but they appear on the left). You can colour the text, label and/or state areas. You can make the line disappear when it is in one state and reappear in another. You can use a MAP transform on the Item state to substitute fancy characters into the right hand area (and also colour them).
But you can’t put an arbitrary image on the right hand side, unless you can encode it as text.