Lord of the Rings: Battle for Middle-Earth, developed by EA Los Angeles (now DICE Los Angeles) was a darn good RTS, enough to warrant a sequel. But that was released 12 years ago. While a third instalment is unlikely, that hasn't stopped a fan project, called Battle for Middle-Earth: Reforged, from attempting a remake.
Battle for Middle-Earth: Reforged is a recreation of the RTS using Epic's UE4, the idea being to use a new engine, but "preserve as much of the old gameplay" as possible. The main difference will be "realistic physics".
Along with "up-to-date 3D graphics [and] FX effects [sic]" the game will support "dynamic and destructible landscapes and terrains" and a focus on "no more lags [sic]" multiplayer.
Speaking of multiplayer, this will be the main focus of development with a campaign possible if "everything is successful".
There's no release date, though a beta version should be available at the start of next year. As for copyright issues:
Yes, we worry a bit, when it comes to [Warner Bros.] and their possible reaction, however, take many examples of non commercial projects of Total War, Skyrim or other engines. We still have an advantage: Unreal Engine 4 is free for non commercial projects, so anybody could play the game for free!
I'm a bit concerned about the use of UE4's license as some kind of shield (which has nothing to do Reforged's use of LOTR IP). We can always hope it, somehow, flies under WB's radar.