I need help with my newborn baby

Good evening. I (a Brazilian woman of non-descendant descent) am in a long divorce process with my ex-husband (of Japanese descent), and in the meantime I became pregnant with my current partner. I've already spoken with the consulate, and to put my current partner's name as the father on the birth certificate, I would need my ex-husband's cooperation in signing "non-paternity" for my baby, but my ex-husband doesn't want to. I saw that I can register my child myself at the Japanese city hall and demand that they don't put my ex-husband's name on his birth certificate. I thought about doing this because eventually I might get married and give my current partner's name to our child, but I have a concern: since I'm not of Japanese descent, my visa expires in a year, and I'm still in the divorce process. Will my baby get dependent status and be able to stay with me in Japan until my visa expires, or could he be deported? Please, I ask for help 🙏🏻

by TrueMobile2449