A popular influencer and champion powerlifter has been arrested for battery ... this after she was previously arrested for allegedly leaking nude photos of her ex-boyfriend's new flame.

Stefanie Cohen Magarici -- a social media personality who goes by Dr. Stefi Cohen on Instagram and describes herself as a doctor of physical therapy -- was arrested Wednesday on a domestic violence battery charge.

We've reached out to law enforcement for more information about the arrest ... so far, no word back.

This new arrest comes amid a flurry of legal troubles for Cohen ... who was arrested last year for sexual cyberharassment.

According to CBS News -- citing the arrest affidavit -- Cohen's ex-boyfriend and his new girlfriend came into a police station in November 2023 and claimed Cohen leaked nude photos of the other woman. They reportedly told the cops Cohen said she did it to embarrass her ex's new GF.

Cohen has more than 1 million followers on Instagram, where she teaches people to powerlift and take care of their bodies, and she posted loved-up photos with boxer Tristan Hamm to the account earlier this year.

We've reached out to Steffi ... so far, no word back.