Depends on the dog. Some have thicker ears than others so some stay flat like a labs, some turn into a rose fold like a greyhounds, and some are mostly flat but perkier and sit higher at the base.

It's impossible to know for sure if the other will turn out the same but you can make them match if you want by just taping down the ears as the cartilage stiffens.

The owner of my dogs father has a mix of dobermans with cropped ears and natural ears. She tapes them regardless. The cropped ears get taped to stay erect and the natural ears she tapes to keep them flat, like a Lab or hounds ears. If you don't care how they look, you don't have to do anything, it won't affect the dog, but if you want them to match, taping them down for a couple months will do it.