ssh server in go : how to offer public key types different than rsa?
I found why the client and the server can’t communicate, the rsa-sha2 algorithms are not yet implemented in the x/crypto library. There is an issue about it on github : https://github.com/golang/go/issues/49952 .
A temporary solution is to add
replace golang.org/x/crypto => github.com/rmohr/crypto v0.0.0-20211203105847-e4ed9664ac54
at the end of your go.mod file, it uses a x/crypto fork from @rmohr that works with rsa-sha2.