I know that converting content from one game engine to run in another game engine is illegal because someone tried to convert Morrowind completely to run on the Oblivion engine and Bethesda denied it.
I'm interested in converting some Daggerfall maps to run with the Morrowind engine because of limitations with Daggerfall engine where dungeons can only have one entry/exit. My interest in doing this is only for toying with Daggerfall architecture and to show others, and not to convert the game or to create a playable mod. In particular i'm interested in using grammar rules and l-systems to proceduraly generate believable dungeons and towns which closely match a textual lore description of the place.
I would have used another game engine but unfortunately the best possibilities (DaggerXL and OpenMorrowind) are still in not mature enough so i would have to use an engine i know how to mod and one that is compatible with Daggerfall architecture (i'm considering writting a software render engine myself but will take at least one year to finish).
This said do you think there are legality issues in doing this?