People probably like different things, but personally I like the potential for intrigue, conflict, passion and helping each other grow. They both have a lot of emotional trauma from the past and and have apparently had to learn to conceal, not feel. So I think there's a similarity, and a possibility for a very great mutual understanding - though at the same time the traumas and their skillsets are so different they could benefit each other and help each other heal and grow. Similar but still different enough to make it interesting.
For example, I'm really intrigued by how Hans knew just what to say to Elsa at the ice palace battle, read & understood her just right to snap her out of it and calm her down. Meanwhile Anna in a similar situation just stubbornly pushes Elsa into lashing out and hurting her, because she doesn't understand how her mind works - so in a way it seems Hans understands Elsa better than Anna does.
Also there's the formidable power couple ruling together thing. And of course the conflicted, forbidden feels and villain redemption aspects, both of which I love.
So mainly it's the latent potential for amazingness rather than the current canon situation, for me.>>82286519