Trademarks
Looking at the USPTO database, there are many trademarks already registered for digital pianos. As such, selecting a name that is not already in use is particularly important, both to stand out and avoid litigation. A possible (temporary) name has been identified in "digivory", as it has not been registered as a trademark.
Copyrights
While there is likely existing code or designs that could be licensed for this design, this is not likely to be necessary. Audio processing is already an area that is fairly saturated with open source code and the unique elements of this design necessitate independent development.
Patents
While there are many patents for digital pianos, including those that interface with a computer, my search of the USPTO database did not reveal any pianos that were designed to be portable in this way. Patents for keyboards include US D1039036 S, US D1042612 S, and US D1026079 S. Special attention should be made when generating designs to not infringe on such patents. Additionally, patents such as US12073144B2 govern communication between a digital piano and computer and should be similarly taken into account in the design phase.