I am an attorney licensed to practice in Virginia and Washington DC. I have studied IP law extensively and I even practiced it for a short period of time (though I do not anymore).

Yes, this mod will violate copyright. However, it appears like it will also be covered by the Fair Use doctrine. The Fair Use doctrine can be found at 17 U.S.C. § 107. In my professional opinion, this mod falls under Fair Use because it is (1) not being created for commercial purposes and (2) highly unlikely to have any impact on the sale of the original copyrighted works. As such, it is my professional opinion that, while this mod will violate copyright, it will fall under the Fair Use exception and thus is acceptable under US law.

Since this is a professional legal opinion, and I'm an attorney, I do of course need to state the following. I am not licensed to practice law outside the United States. This advice does not apply to international copyright law or to any national copyright law. I make no comment whatsoever about whether this mod will violate the laws of another nation or political entity. By giving this advice I am not consenting to represent you in any court of law or before any other legal entity. This advice is predicated on the information provided to me by the above posters. Any information which was not included in this thread before I posted has not been considered and may change the legality of the mod. I advise you to consult a licensed attorney in your place of residence before engaging in any activity that may violate a law of your locality, state, nation, or governing body.

Have a nice day.