They have nearly the same temperament.

I agree Wavesurf. They would get along quite well.

Similar to Jasmine and Mulan, I think Ariel might be too rude for Mulan, even more so than Jasmine because Ariel ignores people and moves on to a new activity while other people are right in the middle of talking to her. I don't think Mulan would like that blatant disrespect, even if she thought it was unintentional on Ariel's part. Also Mulan seems to have way more loyalty to her family even though Mulan has parents who are far more strict than Triton is with Ariel. Mulan seems to be a very grounded personality and I don't think she'd have that much appreciation for Ariel's very flighty and more opposite personality.

In a loose sense because Mulan is the type who would try to get along with everyone, but it would be mostly one-sided. Ariel prefers friends whom she shares things in common with or she finds exciting, and Mulan doesn't fit the bill. she isn't romantic, playful, adventurous, loud or anything Ariel likes. and Mulan would prefer many of the other girls to Ariel, I think. she would like Ariel in a basic way but probably find her very foolish.

I think they would be more or less neutral towards each other.