While Reg. AA has been repealed, the FTC has not repealed their requirements:
https://www.law.cornell.edu/cfr/text/16/444.3Even in the Interagency Guidance that was issued at the same time they issued to proposal to repeal Regulation AA, the regulators indicated:
The Agencies note that the FTC’s Credit Practices Rule requires—and the former credit practices rules applicable
to banks, savings associations, and Federal credit unions required—creditors to provide a “Notice to Cosignerâ€
explaining the cosigner’s obligations and his or her liability if the borrower fails to pay. The Agencies believe that
creditors have properly disclosed a cosigner’s liability if, prior to obligation, they continue to provide a “Notice to
Cosigner.â€
It didn't actually go away.