This is the template file used when outputting the username field, and the highlighted action is what you can use to output your own password input HTML field:
https://github.com/Automattic/WP-Job-Manager/blob/master/templates/account-signin.php#L52
This function is then called on submission of the form to create the account:
https://github.com/Automattic/WP-Job-Manager/blob/master/wp-job-manager-functions.php#L358
Then check if they provided a password and return an error if not through this filter:
https://github.com/Automattic/WP-Job-Manager/blob/master/wp-job-manager-functions.php#L409
You will then need to use the filter on the account data, and use the value in $_POST for the password:
https://github.com/Automattic/WP-Job-Manager/blob/master/wp-job-manager-functions.php#L425
You will also need to override the default WordPress new user notification email as the default flow for WordPress is to now send a lost password reset link instead of standard email with account details.
I’m going to add this feature in my Emails addon plugin in one of the upcoming releases (feature is not available yet) … but if this is really something you want to do, I’ve already done the majority of legwork for you above by detailing everything that needs to be done to accomplish this. Good luck.
