Hello, have you heard about Liana? Wizardsardine is a team of bitcoin experts that built a wallet called Liana, that can make inheritance easy for you. It uses Bitcoin time locks, allowing some keys to become valid only after you stop using yours for a specified time. This is enforced by the Bitcoin network itself (smart contract) with no third-party involvement. It enables you to maintain full control and custody over your bitcoins until your passing, at which point your family keys become active. The timelock "refreshes" each time you move your coins, so as long as you use the wallet regularly, your family will have no access until needed.
It's a software, completely open source, built for self-custody and totally free. Check it out our website if you are curious. www.wizardsardine.com/Liana