Thank you for your interest.
At this moment the implementation of the chart does not allow to position the labels inside the plot area. As a workaround I can suggest that you use TextBlock annotations instead of labels. You can take a look at this
article from our online documentation demonstrating how to add annotations to your chart.
I hope this will give you some ideas and let us know if we you need further assistance.
Have a suggestion or face a problem - you can use the Ideas & Feedback portal
to submit ideas, feedback and vote for them.