What would the relationships between the princesses be: 신데렐라 and Merida?

That's interesting...I think it's the same as Elinor and Merida's relationship

Cinderella- *working*
Merida- Let's get out of here >3> too dull and boring
Cinderella- O....O no
Merida- Pfffft, once boring always boring. Peace

Merida would be bored with 신데렐라 and think she's spineless for never standing up to her stepfamily. she wouldn't like how traditionally feminine 또는 responsible she is.

신데렐라 would find Merida an immature brat and would probably 사랑 to see her try that with her stepfamily and see how long it lasts =P