The Microbots in Big Hero 6 remind me of this concept: https://www.youtube.com/watch?v=dSkuzg7YCo8
The bandwidth required for the proposed system in real-time is prohibitive using today's communication technology. What is needed to enable this is Terabyte-to-Petabyte level comms bandwidth.
The logistical challenge associated with a large 3D printer that does not use materials found locally is untenable. What is needed is a compact solution that is able to utilize materials found in the local environment for 99%+ of the structural mass. See "Super Adobe Bots" in the Imaginarium for just this solution.
This is an interesting concept, and could be made even more powerful by including a model of an individual's personality (i.e. executed on a neuromorphic CPU), which is further described in the Spark "Autonomous Culturally Adaptive and Intelligent Avatar Agents." A tool such as a digital twin with a realistic model of an individual's personality would be extremely useful in gaming out critical situations in which outcomes hinge on the judgement of a single individual or small group of individuals. Example scenarios include: treaty negotiations, war gaming down to the individual commander/actor level, and personnel selection for critical postings. I envision the concept only being employed in critical situations. Limiting use to a small subset of critical situations, scenarios, vehicles, individuals, etc. would help mitigate the cost associated with the difficulty of implementation. Digital Twin is a much catchier name than "Autonomous Culturally Adaptive and Intelligent Avatar Agents," but the two ideas are highly complementary and similar.
An interesting path to pursue would be embedding bio-compatible sensor suites with the tissue to deliver real-time information about the progress of the implanted organ or skin to aid the medical staff in the prognosis. The sensors could autonomously transmit signals to drug delivery systems and update databases with vital information. Embedding the sensors could be a part of the hi-fi 3D printing process.