Checking here, on a Tumbleweed system:
“/usr/libexec/ssh/” contains:
ksshaskpass
ssh-ask-pass
gnome-ssh-askpass
Checking my environment, I find:
SSH_ASKPASS=/usr/libexec/ssh/ssh-askpass
The script that I use for loading a key, sets
SSH_ASKPASS=/usr/libexec/ssh/ksshaskpass
in the environment (if my desktop is KDE), and the result is that “ksshaskpass” is called for the password.