It just dawned on me that you could possibly legally sell mods to games as long as it is an addon and not modifying the executable. The skins can be legally sold for sure it's the modified text documents that make em work that would be the grey area in selling them. Making the buyer of the skins manually making them compatable. I'm not familiar with the end user agreemants as I never read them. So for the EULA in RTW, I believe it says the executable is not be modified w/o consent and modifying the other files is allowed and has there legalities with description. So it would be how the EULA can be interpreted to allow the selling of the other modified files.

Next would be the lawyers to deal with. They and the company are backed with money and you are not. So even if you can legally do it, you don't have enough money to prove you can legally do it.

On top of that you'd be ousted by many internet communities and there would likely be none to buy it, therefore saving you the lawsuit due your not really tapping the developers revenue. If somehow it became successful, you can rest assure yourself letters for court appearances.

You can make a game for a console and legally sell it. Many items are sold as addons to something another manufacturer made and in just about all cases no royalties are paid.

The only other part is if your work was used and sold, you can make the sales cease, if you can prove you are the one who did the work.