>>46032765legally "unlikely", at least in Japan.
Much like with art, voice belongs to a real person and can only be licensed for commercial use. Once contract ends, the company loses rights for further use of that voice unless stated otherwise in contract
( this is why vtuber archives gets cleaned )
in case of death, rights for existing works would be passed onto next of kin, thus a new contract would be required in order to keep using the voice.
But it is extremely rare to get rights from family as it is considered morally a really dick move to cash in on dead relatives
(Not even hollywood has managed to secure rights for passed away singers/actors and they sure have tried)