of course, you are only a shareholder of a restaurant, whether you join an existing restaurant or open another one in your own name or in your wife's name.

There will be a problem here. You are a minority shareholder in an existing restaurant. Usually, it is difficult to protect the rights and interests of minority shareholders. If it is not protected, you may have to exercise the shareholders' right to know. If you exercise the shareholders' right to know through litigation, because your wife is a shareholder of a similar store, or you are a shareholder of a similar store yourself, it will easily be regarded as an abnormal purpose when you exercise the shareholders' right to know, which will affect your exercise of the shareholders' right to know.

although I don't know the nature of your restaurant business, you used the term "shareholder", which usually refers to a limited liability company or a joint stock limited company. If it is a partnership, you are not called a shareholder, but a partner. No matter what it is, some people in limited liability companies, joint stock limited companies, partnerships and other enterprises are exercising shareholders' right to know through litigation.

Therefore, it is suggested that you open another restaurant in someone else's name. It is better for you or your wife to be an anonymous shareholder. If you accept this suggestion, you'd better find a professional to help you draft a share holding agreement to avoid unnecessary disputes in the future.