Sorry to not address the bulk of your comment, but overneath is a fascinating word, for someone interested in languages and the process of foreign language learning specifically. It’s entirely understandable, but not a real word as far as I can tell. I’m interested in being corrected here, for sure. Seems theres a company by that name but thats all I was able to find.

Normally in this context you'd see overtop, overhanging, covering, above, over, something like that, but overneath makes total sense too, due to underneath and beneath being words with the widespread definition of under.

I did find that ‘neath’ is a shortening of beneath which means under, and under obviously means under, so underneath is technically redundant and means “under under”. And overneath would actually mean over under, which is itself kinda fun, because of how understandable it was in context. :D