Consider pointing to jsch fork
https://github.com/mwiede/jsch is actively updated and has some fixes and features, notably ed25519 keys.
@nivekuil I was able to connect and execute ls with this fork but also found other alternatives. maverick-synergy is actively maintained and has a pretty straight forward API to use via interop. sshj might also be of interest.
I bumped today into this issue when trying to connect to a server with ed25519 keys too. Similar issue seems to exist in gradle: https://github.com/gradle/gradle/issues/19028
Another way to use the fork is putting in your deps.edn:
clj-commons/clj-ssh {:mvn/version "0.5.15" :exclusions [com.jcraft/jsch]}
com.github.mwiede/jsch {:mvn/version "0.2.8"}}
Fixed by #68