Is it possible to create a user account in appian without email id?

email is a required field for an Appian user. You can add a dummy email address, but that could have some drawbacks - users couldn't manage their passwords unless you are using some external SSO. Task notifications and other system events would be sent the dummy address, so you would have to be mindful of spam, etc

We are using sso.so changing password should not be an issue. the only way I see is providing a dummy email id which need not be an active one.

Can you please explain your Use case. Do you want to restrict users to change password from "Reset your password " option.