python-shamir-mnemonic VS python-shamir-bip39

You can recover with regular Linux/MacOS/Windows computer using this python script https://github.com/trezor/python-shamir-mnemonic

I suggest you do some further reading here https://github.com/trezor/python-shamir-mnemonic/issues/15

You can use Electrum or any third party wallet to enter the seed phrase. Otherwise with Shamir use https://github.com/trezor/python-shamir-mnemonic/

For even more security, shard the mnemonics with Shamir's secret sharing.

I do hope multisig gets easier in the comming years, but just the same, Shamir could also be standardized (the trezor team has already done the work and has the proposal and implementation) in the same way.

I mention that in the issue. The problem is this rationale seems unjustified because a 12-word BIP-0039 mneumonic encodes 16 bytes (128 bits) + 4 checksum bits of information before the passphrase comes in https://github.com/trezor/python-shamir-mnemonic/issues/40

However, the trezor reference implementation only allows to be given an existing secret in the form of hexadecimal seed key and not the actual mnemonic, as provided.

Trezor support Shamir backups (at least the model T does), but the cold wallet itself should be stored in the safety deposit box with the bank too (because if you know the device password and have the wallet with you then you are vulnerable to a wrench attack). You can generate one for an existing seed phrase with this command line tool also: https://github.com/trezor/python-shamir-mnemonic/

That's the implementation by the way: https://github.com/alandefreitas/python-shamir-bip39