What's your Power BI desktop version? In my test, there are only four items "Axis","Legend", "Value" and "Tooltips" for a Clustered bar chart. What does the highlighted one refer to in above image? Please translate the highlighted one in English.
This is last version 2.64.5285.741
buy the photo is from powerbi online
highlighted one is colour saturation
the old version of power bi desktop we are using this
https://www.youtube.com/watch?v=yuPPK7sDLqU&t=539s in that video minutes 8:37 we can see this