I wouldn't have them age out as thats alittle boring. As cliche as it is he deserves to go out fighting like a warrior against insurmountable odds. I would have his son or daughter brought in and kidnapped with him going to save them versus a Cosmic level group like the Black Order. He dies from a fatal wound after saving his offspring and they become ruler of wakanda. Id go with Azuri.
Storm doesnt have to be involved though lol