This is an amazing achievement for a two-week jam! The scope really is on par with those classic adventure games from the 90s--it's very extensive and satisfying. I enjoyed the story and the puzzles were tough but fair. The English could be smoother, but that's something you can polish more after the jam. I also appreciated features like item highlighting and quick travel.
I like the mechanic of switching between the characters, but it felt underutilized because almost everything falls on Marco anyway--I'd suggest either removing the mechanic and just making Sara and Andrea NPCs, or finding a reason to have Marco be stuck somewhere for a while so someone else can walk around for a while. But that's just my opinion.