If they decide to use Death, then I don’t think they will give him a speaking role. He will probably just be another obstacle the gang must overcome*, which I’m not too sure how I would feel about that because it is technically still accurate to the character itself
Death didn’t have any dialogue at all in the Aria/Dawn of Sorrow games, which was odd considering how the overall narrative of the series lore expanded upon him by showing his utter loyalty to Dracula & his manipulation of events/characters. So if the show omits his “personality,” it’s going to be kinda weird, but kinda not at the same time
*unless they include him as Zead, which is possible although that may be too “on the nose”