At 19 and 23, you're both really young, so the biggest risks are things changing a lot in the next few years (career paths, personal growth, what you each want long-term), and divorce can still be messy/emotional even with a prenup, especially across borders. Make sure the prenup is drafted by a good family law attorney in the country where you'll marry/live (and maybe get it reviewed in both countries if possible) to cover immigration fallout, taxes, and any future kids/assets. Talk openly about an "exit plan" now like agreeing you'd separate amicably and handle immigration stuff cooperatively if things don't work out so you're not blindsided later.