You have the --non-interactive option. From the man page:

Switches  to  non-interactive  mode. 
In this mode zypper doesn't ask user to type answers to various prompts, but uses default answers automatically. 
The  behaviour of this option is somewhat different than that of options like '--yes', since zypper can answer different answers to different questions. 
The answers  also  depend on other options like '--no-gpg-checks'.

There is no real correspondense to apt-get's autoremove. The closest is the --clean-deps option of the remove command, which cleans dependencies right away.

You have the --non-interactive option. From the man page:

Switches  to  non-interactive  mode. 
In this mode zypper doesn't ask user to type answers to various prompts, but uses default answers automatically. 
The  behaviour of this option is somewhat different than that of options like '--yes', since zypper can answer different answers to different questions. 
The answers  also  depend on other options like '--no-gpg-checks'.

There is no real correspondense to apt-get's autoremove. The closest is the --clean-deps option of the remove command, which cleans dependencies right away (but not afterwards).