Hi, yesterday, I found a free assert from Unreal Engine 4 [FREE] Assets, which is called substance materials free pack, I click on the link and I find out it is from Gumroad, it is free but I am not sure if this assert is able to use in a commercial way, the designer of this package said that: “Substances and exported textures may not be redistributed or resold unless embedded components of electronic/interactive media.” I am wondering that if I can use this assert in my game which is for commercial use. Sorry for my bad English, thanks. The link to this assert is Substance materials free pack
i would guess that means you can use them as you like in your game as long as your not selling the individual assets. you may want to check the actual license or contact the seller though.