ssh / sftp could have wildcards in file known_hosts for bunch of servers with same key, aka: [10.*.*.*,172.22.*.*,!172.22.16.1]:1022 ssh-ed25519 But when I connect from krusader to such a server, a new key must be accepted and is added to the file: [172.22.20.24]:1022 ssh-ed25519 Also shouldn't it use known_hosts2 as ssh uses?
It's quite likely an upstream shortcoming as the SFTP KIO slave uses libssh which seems to neglect a lot of "convenience" features. For example what you want to achieve here could be also done with HostKeyAlias, but that isn't supported either. Apparently it doesn't use known_hosts2 by default, but surprisingly it supports the UserKnownHostsFile option, so you can request that to be also used in your SSH config file.