I made a Billie Eilish sim today and I think she looks quite similar in my opinion.. let me know what you think!
I got the accessories , ,
I got the hair
Baggy tshirt, but I recolored it black is found
The shorts are from
Eyebrows are from
I made the eyes, and the skin was from
Did I miss anything? (EDITED TO INCLUDE Mod The Sims Download) Also, it's likely you may need the meshes from some of the above links
Again, I'd like to hear what you think.