I am looking for CAPTCHA implementation or configuration in AngularJS project without using the reCAPTCHA concepts.
Check Visual Captcha which is self-hosted and supports AngularJS.
Check this for supported front and backend
Update [31-03-2021]: This project is not actively developed anymore.
AngularJS captcha -recaptcha, but perhaps you can tell us why you don't want to use recaptcha ?