With the security enhancements to NetCommunity 7.1, password  encryption was improved. The only option in a User Import is for the system to auto-generate an encrypted password for the record. In order for new users, added from a User Import, to gain access to the site, they will need to visit a page with a User Login part and click the link to reset their password.

The automated registered user email generated from the User Import can be configured to include a link to the password reset page.
If your organization already has a Registered Users Template,  you can work from that. You can confirm if there is an existing template via: Email>Template>Filter by data source: Registered Users. If you see a template you like, you don’t need to build a new one, unless you want to. If you don’t see an existing template for Registered Users, create a Registered User Email or Email Users from a User Import