Setting up a business - l’activité principale comporte la création d’une œuvre de l’esprit?

I am a dual citizen (France/US). I am interested in setting up a business in France that would create artistic productions, such as novels, screenplays, videos, short films, etc. I would like it to fulfill this definition:

Ce dispositif concerne les artistes-interprètes et les auteurs d’œuvres littéraire ou artistique, titulaires d’un contrat de plus de 3 mois avec une entreprise dont l’activité principale comporte la création ou l’exploitation d’une œuvre de l’esprit.

1. Would you please give me advice on what type of company to form? Would it work as entreprise unipersonnelle à responsabilité limitée (EURL)? I wouldn’t necessarily have clients immediately. It would be more a company that produced novels, screenplays, videos, and so on. Is there a better type of company to form? Is there a way to keep it separate from my personal finances?

   Initially, the company would just consist of me, but I would then like to hire my sister from the US as an employee to work on creative work. It seems that I could possibly hire her with a carte compétences et talents as an auteurs d’œuvre littéraire ou artistique. She has an MFA and many years of experience in the industry.

2. Do you have any other advice on hiring my sister in this kind of company? I know I may need to see an immigration lawyer, but I thought I would ask if you have any thoughts.
3. I have the option of starting the business from either the 92 or 75 prefectures. The employee (my sister) will be living in 75. Does it make more sense to start the business from 75, so all the paperwork (Demande d’autorisation de travail pour un salarie etranger - contrat de travail simplifie CERFA N 13653*01) as well as the employee’s carte competences et talents would all be dealt with by the same prefecture?