The best way to start exploring the conversion process from AppMon 7.0 to Dynatrace is by contacting your local Dynatrace resource. They can walk you through all of your questions and help you understand the process of converting licensing from AppMon to Dynatrace.
Hi, find your local Dynatrace resource here: https://www.dynatrace.com/company/locations/#asia-and-pacific
In the meantime there is nothing stopping you from using the free trial. Let your local resource know you are taking part in the free trial and I am sure they will help you make the most of it.