>>122508779I got an idea.
Arendelle vs. pirates.
Okay hear me out. So the background story that I heard for Hans is that- aside from a childhood with 12 brothers- he was a naval officer. In fact, one of the original ideas for him was that he would be an admiral. So let's take that information after his exit from Frozen. He goes home, receives menial tasks from his family and is now disgraced as a prince. However, he is still respected as an officer. He either falls back on his old comrades for support or his family sends him back or something (I dunno, it's Disney and will probably not make sense). His old companions actually don't care about his prince status, Hans is good with a sword.
Well word goes around that he's back in the military (? I dunno what to call it lol) and it upsets Southern Isle citizens that such a bad man is allowed back so they ask the king- Hans father- to take him out of it. But Hans is against that. Some disagreement happens between Hans and his father. Hans leaves, and so do the old comrades that have supported him. They become traitors to their country because they stole one of the king's ships. End act 1, because we get to see Hans living out at sea and fighting Norway mythical sea monsters or something.
Anyway, probably in good spirits one day on the ship, they mention Arendelle in a conversation and Hans suddenly hatches a plan to take the country from the inside out. He knows that Arendelle has recently seen a spike in immigrants and that they're foolish idealism means that they'll accept anyone.
Cut to Frozen 2, and Queen Elsa is gone. This information gets relayed back to Hans. It's time to attack. They take the castle, Kristoff and Anna escapes to search for Elsa.
Anyway the villain isn't actually Hans. It's been brewing that Hans and some other naval comrade have been having disagreements on Hans' leadership. This person plans to take the kingdom from Hans and convince the crew of mutiny.