What are some options to pass on your self-custodied crypto in the event of an unexpected death?

As the topic says, I am doing full self custody, with no one besides myself knowing any of my seeds.

Is there an option to do this without actually passing on my seeds now? I am worried that the people, that I otherwise fully trust, might not be careful enough with them.

I would prefer to continue being the sole person who has access to the keys, but I am of course interested in passing it on, in the case of an unexpected death.

I have been doing some thinking on options, but I would like some inputs, as I fear the funds being stolen or lost by any third party (like a lawyer or bank), which seems like the otherwise obvious method.

Some of my current ideas:

• Putting in a secret, and hard to decipher message in my will, which would enable any of my close relatives to locate my seeds.
• Using a Shamir seed to split the seed between trusted people in my life, and leaving some to a lawyer or in a bank box.
• Using a dead mans switch to send an encrypted email containing my seeds to people who are given the passwords in advance.
• Getting a stainless steel implant in my scalp, which can then be extracted by a trusted person upon my death (/s)

But seriously, how could it be done?