If you are planning to sell materials/textures these need to be 100% your own and not include the original texture.
For example, you are permitted to take a clothing mesh from say CC Essentials or the Professional Outfits pack and create a new set of materials for it and then resell it. This will then be considered derivative content and the customer will need to own the original clothing base mesh to be able to use the content without a watermark. However, you can't sell the clothing with only a modified texture because the texture is not yours to sell.
Peter
Forum Administrator
www.reallusion.com