Yes you can draw a trend line in a scatter plot. Unfortunately you can`t use the same easy way like in Qlikview. You need to create a reference line and use an expression which calculate the trendline (y=mx+b). linest_m & linest_b functions also work in qlik sense.
Please see following posts:
Did you get the answer?
I have the similar case and would like to know the following:
1. Which reference line should we add: X-axis or Y-axis?
2. how to write the expression? Right now, I can only get a wrong straight line with LINEST_M([Win Rate], [Distance (KM)])
Can Ronny or anyone else help?