I haven’t gotten any unreal engine marketplace content just yet. I am planning on creating a simple scifi shooter game but if i were to get some scifi environments and that was the main thing you saw in the game(walls, floors, props) and i managed to publish it, would i get a copyright fine of any kind due to that content being made by another person? Could i combine multiple content by other people and make it all just one? Thank you to all of you that can help me out. appreciate it. 
Hi Zeldaboy427!
Any content you purchased on the Marketplace can be used for commercial use. All content under the name of “Epic Games” can be used for commercial use. but must be created within the Unreal Engine. Let me know if you have any other questions. I will be happy to help!
Kind Regards,
-Reubitron