We shave the scalp before the hair transplant surgery. For this reason, there is no significant difference between straight and curly hair. The donor hair is also not majorly different in people with curly or straight hair.
During the hair growth, hair grows identically with the patient’s natural hair type – if they have curly hair, the growing hair will be curly. If it is straight, the newly growing hair will be straight.
Because of this, neither the hair transplantation or the hair growth after it is not disadvantageous for people with curly hair.