Thank you for your compliments.
However, I'm not a trader, but a long-term private investor, and I don't have a GmbH or SA.
I think that if you want to set up a company, the best thing to do is to contact the commercial registry directly. But if you're looking for financial independence, you don't need to do that.
In this case you just have to :
1) if your spouse is not already insured for AHV, register with your compensation office as a person not in gainful employment (you will be taxed according to your assets):
https://www.ahv-iv.ch/p/2.03.f
2) take out non-occupational accident insurance with your health insurer. In principle, you don't need loss-of-earnings insurance in the event of illness, as your income is assumed to be passive.
3) be taxed on your dividends and possibly on capital gains if you are recognized as a professional:
https://www.moneyland.ch/fr/gains-boursiers-actions-impots
The criteria listed in the link above argue strongly in favor of a long-term investment orientation, to avoid being categorized as a professional and paying capital gains.
A++
Jerome