Hello
Router os: 6.47.9
user: 'abc'
pass: 'any'
Can connect from any machine by ssh. Correct.
Import ssh key for user 'abc'
Cannot login from any machines without priv key
Should be - if there is priv key - login without password
If there is not priv key - ask for password (RouterOS ask) and if password correct - let to get into the system. RouterOS not allow. Just ask again for password
Best
Sylwester