How do I create a scan for the moving average crossover to the downside of stochastics in the overbought condition > 80  or

Crossover moving average of stochastics to the upside from below < 20

You would click on the Stochastic %K indicator and select Create Scan Condition to create a condition for the Stochastic %K indicator being Greater Than 80 and another condition for the Stochastic %K Crossing Down %D.

Create Conditions from Your Chart

Then you would add both conditions to the same EasyScan.

Building a Scan with Multiple Conditions

You would do the same thing for the other EasyScan except that the conditions would be for the Stochastic %K indicator being Less Than 20 and Stochastic %K Crossing Up %D.