I hope you could give this question a try before closing it. It's, admittedly, not directly related to German, but if a successful answer is provided, I'm sure it will be useful – at least for German learners – in finding counterexamples. Moreover, if I pose it in other site, I'm sure it will be closed faster.
There are some answers providing search techniques that are incredibly easy and very useful:
The thing is that I've tried to search in Elexiko, say, words ending in
-ung that are masculine. Surprisingly it provides nothing. In Wiktionary every word is nicely indexed and free access. Hence an analogous search should be, in principle, possible.
- Does there exist a way to perform that "advanced search" in Wiktionary?