After playing around with the properties I started getting strange errors while running test cases. For example unable to create AxisServce from ServiceEndpointaddress.
So after thinking about it. The best practice is to fix the end point per Soap UI project. Trying to change it will most likely not work or will only work after a considerable amount of configuring/testing/debugging.
If you need to run tests against another endpoint you can create a new empty project starting from the new end point and then recreate all test cases. A little bit strange but I suppose this might suffice in some cases.