If I add fuel flow to it, the graphs go below the view in the browser. Is there a way to collect different units on the same graph? I have tried the History Explorer card, but that won’t show different units either. I know the number on the graph will be meaningless, but that doesn’t matter.
Look into the history-graph card. One of the built-ins. Otherwise there are custom cards that do many things found in GitHub. Search for those using the HACS loader.