BSK Forms Blacklist supports Gravity Forms, Formidable Forms, WPForms, Contact Form 7, and Forminator.
It is not a blacklist tool but also can do white list, Email list, IP list, invitation code list. You may check the BSK Forms Blacklist demos for from the below.
Gravity Forms
Blacklist to block spam submission
White list to only allow invited people to submit
Email list to allow invited emails or block emails. Support email domain name validation
IP list to block all submission except your organization
Block submissions from Canada
Whitelist submissions from Canada