He says he is inspired by other artists hairstyles or pictures. The following text is directly from only hair he posted on Patreon from David so far was Milky Way aka Mecca. Left = David’s hair, Right = Sonyasims’ hair

If you compare Carmen’s topology to Climate Change (his hair) you can see it’s closer, just keep in mind that his meshes are edited and smoothened. In the pics you all are seeing raw 3ds file but you call can get the packages and compare them in blender. When I took these pics I used my Perfect Illusion hair as comparison, but if you take Carmen hairstyle it’s even easier to find similarities because I didn’t even decimate that one. For now we just spotted 3 different creators. I will make you a favor and prove that all meshes aren’t yours, also no lawyer needeed, whatever amount you had in mind to give this lawyer for its job, you can split it and send it to all the creators whose creations you used. Oh and I am sure from now on you will be careful with which mesh you take, because we all have our eyes on you. If you respect someone you don’t steal its work and claim it as yours, or edit it to make it look a different thing. There’s a BIG difference between being inspired and literally rip off someone’s work. Here you can see what he told to his patrons. So, as it seems, Sonyasims trully believes that he didn’t steal any mesh, he hasn’t used any as base, but I’m just pissed of this attitude. I wasn’t sure which image post as header, because you change this private post in your patreon whenever you want.

Sims 4 two braids