Tedious, yes. But fairly reliable and you don't have to place any trust in your attorneys at all, unless they find out who their counterpart is and start working together (very unlikely). If this system wouldn't work for you, you've probably got bigger problems than having to worry about your wife getting into your email after you die.
Personally, my wife would wonder why I'm going to so much trouble to keep my passwords secret from her until I die; but then my personal password store is for services we share like banking, and any passwords she doesn't know are benign things like my email addresses and various website logins that wouldn't matter anyway when I die. Of course I also have my work passwords (I'm the IT manager), but my supervisor and the company owner each have a secured store of all of my work passwords as well, plus the master password to access them, in the event something happens to me (or I'm just on vacation for a week and temporarily unreachable when access is needed).
Much less tedious, and concentrates trust in the one person who should have it - the spouse!
A bit of research might be indicated, before trusting this strategy to perform when needed.