Google offers Inactive Account Manager and Apple has a Legacy Contact feature. They are worth setting up, but they work at the level of a whole account and do not let you precisely control who sees what, or leave organised instructions. Treat them as a supplement, not a plan.
Put your most important documents in one secure place
Sejf Życia is an encrypted space for documents, access details and instructions for loved ones. Only you decide who gets access, and when.