How to create a query that follow trend (line chart) of another query.

[Rao_KGY]

I have a panel in a dashboard that plot a trend line for last 24 Hrs. Now I wanna create a new alert query that should follow the trendline of panel.

If the output of alert query doesn't match (not exactly but to an extent) the pattern of panel query then it should trigger an alert. 

[ITWhisperer]

For anomaly detection, you should  consider using the MLTK.

Otherwise, you need to fashion a report which detects anomalies and use that for triggering you alert. In order to do this, you need to be able to define what an anomaly looks like, so that you can instruct Splunk to find them for you.