This is the Sci-fi level i created in Unreal engine 4 with original modular set of models. I used substance designer and painter for the all the textures and procedure materials. Zbrush for all the creatures sculpting. 
I'm focusing on the story telling in this level by adding details like notes, posters and text on the board : " The person who lives in this bedroom is an alien creature biologist. he likes music, queen is his favorite band. But one of the creatures escaped from the container, and things got out of control." 
Check out the breakdown article I wrote for The Rookies and 80 level https://discover.therookies.co/2020/06/16/how-to-create-an-environment-level-in-unreal-engine/
https://80.lv/articles/escape-texturing-and-lighting-a-sci-fi-scene/