Is it challenging to correct mild dysplasia during hip replacement? what is considered the desired alpha angle post-placement?

No: The challenge in correcting hip dysplasia occurs when you are trying to realign and spare the joint. When performing a total hip arthroplasty, you can position the hip however you want. Dysplastic hips may have shallow sockets and pose a challenge to replacement. See a board certified orthopaedic surgeon, who specializes in adult reconstruction.