MUP setup auth failed with ssh key based on ed25519

Anyone knows how to circumvent this? I always get the error, that the ssh2 module can’t parse the key as it is in unknown format (I am forced to use a shh keygen with ed25519 and can only login to my server using the key, no password login allowed).

There is an issue open, where it is said, that ed25519 is not supported and I have to manually solve this. That’s a good one, as I am totally out of control to handle this “manually”. Am I locked out from using MUP now?