The new password sharing feature only applies to those stored in Google Password Manager, the company’s service that natively stores your passwords and passkeys on Chrome and Android and is linked to your Google account. As of today, the new password sharing feature works on mobile devices – but apparently not yet through Chrome on desktop. After you share a password with one of your family members, a copy of it will be saved in that member’s Google Password Manager.
You cannot use this feature with people who are not in your Google-sanctioned family group (which can only have up to six people). Therefore, if you want to share a password with someone else, you will need to use Near Share to hack it yourself or use more rudimentary and/or less secure methods.