I have discovered functionality to switch series (lines) on/off by mouse click on to the legend square in the chart head (see the orange line/legend on the charts below).
Unfortunately, the change is not persistent. After 15 seconds approximately the series returns to its default.
Not understand your question really. I am feeding standard dashboard graph node with 5 inputs msg.topic=series name (displayed on the top of the chart with small square), msg.timestamp=timestamp, msg.payload=temp.