i am looking for a view that show me on which VM´s in the last 30 days the VM disk was expanded.
Is there a possibility to create such a view? Also to create a monthly report for that?
That's probably not something vROps is going to be capable of showing you because there's no metric or property collected which shows that. A disk resize is a task performed on a VM object and not a property thereof. If you're on vSphere 6.5 that has much better verbosity in tasks that are performed, you may be able to get this out of a custom Log Insight dashboard if you have the vSphere integration set up properly.