WOW Sunni converting to Shia, sounds very scandalous. I don’t think you can truly convert to Shia. You are a shia or you are not. Kher. Best of luck. Just like being a Jew. You are either a jew or you are not. You cannot convert to being a Jew. There are certain things involved.
In my family, we never marry Shias. If I tell my mom hypothetically speaking that I want to marry a Shia, I am dead.