(If you don't have a hardware wallet, you can think about it.)
even if this is something feasible ( it's stressful and a long process) this might only solve the problem of theft when it comes to storing your seedphrase. Most times it's even difficult for someone to get your seedphrase if you store them properly. The major or key reason we emphasize on keeping your seedphrase well is so it doesn't get lost or damaged in the process of keeping it safe. With this your method, it's most likely not going to keep your seed safe but in danger.
We can just stick to the regular mean if storing our keys, and these methods have been tested and trusted by the community. No need for many long processes..