> one-time-use combinations of three English words
I really don't think that this is secure.
> nacl/box and nacl/secretbox
Both of which use XSalsa20 - which while not broken there should be no reason to use it rather than (X)Chacha20.
I really don't think that this is secure.
> nacl/box and nacl/secretbox
Both of which use XSalsa20 - which while not broken there should be no reason to use it rather than (X)Chacha20.
XSalsa20 is indeed fine, but XChaCha20 is better in every way. The proof for XSalsa20 provided by Bernstein applies to XChaCha20 as well.
Magic Wormhole uses a PAKE to establish a secure channel from a low-entropy shared secret.