I am working on a mod for FONV and I would like to convert a few statues and display cases from oblivion to Fallout New Vegas. Would this be illegal or cause any sort of trouble. I would credit the developers of oblivion when the mod is done. Who would I have to contact if I where to ask permission to Bethesda for their things? I asked on several other forums and some people that Bethesda considers that piracy, others tell me its OK as long as I dont publish the mod and some tell me there is no problem.

You cannot use the assets from one game in another, even if both games are from the same company and whether you own them both. End of discussion on these forums.

It is illegal to take content from one game and put it into another.