Depends if it's just the hydraulic block being replaced, the electronics unit, or both together. Just the hydraulic block will be fine. No special skills or equipment needed for that but if the electronics module is being replaced then the new one will need coding, which needs dealer level diagnostic equipment or a near-equivalent such as VCDS.
A used replacement may or may not need recoding depending on the spec of the car it came off but it's always a good idea to check the coding regardless.
A VAG specialist will have something suitable to do this but a general independent garage or mobile mechanic may not.