Alexis Ozanne, one of two young men charged with bashing 43-year-old Stephanie McCarthy, received 150 hours of community service and an 18-month good behaviour bond after pleading guilty to one count of assault and one count of affray.

He was also convicted and fined $600 for cannabis possession.

In Newtown Local Court, Magistrate Anthony Spence warned the 22-year-old he was "perilously close to a jail term" and he needed to get his "behaviour in check."

Ozanne's lawyer told the court this was his first violent offence, though he had previous convictions for property damage and drug possession.

The court heard Ms McCarthy, a transgender woman, suffered "substantial injuries" including a fractured eye socket after Ozanne and his friend Nicholas Wells set upon her inside the Town Hall Hotel on Newtown's King Street.

CCTV footage showed Ms McCarthy walk past Ozanne and Mr Wells around 12.30am on June 6, when one of the men reached towards her and pulled her ponytail, the police fact sheet stated.

When Ms McCarthy confronted the men they denied pulling her hair and blamed it on another hotel patron. She then prodded both men in the chest and grabbed both of them by their shirt collars before letting them go.

Described by his lawyer as a "gross over-reaction" to Ms McCarthy's conduct, Ozanne then punched her in the face, splitting her skin open on impact and causing her to fall backwards. As she was bleeding, he then punched her another two times, in the side and back of her head.

The court heard Ms McCarthy armed herself with a plastic schooner and charged towards both men.

Mr Wells put Ms McCarthy in a headlock, and punched her "upper-cut style" in the face three times, while Ozanne reached over the top and punched her in the back of the head and her back five times.

Mr Wells then climbed up onto a table and unleashed a tirade of transphobic abuse and threatened to stab her.

Ozanne fled the hotel and was arrested six days later at his Balmain home.

When interviewed by police, Ozanne denied attacking Ms McCarthy while she was in a headlock, but eventually conceded after he was shown the hotel's CCTV footage, telling officers he did so because he felt "the whole pub was attacking both him and Mr Wells."

When police asked about the bruising to his middle finger knuckle he told them he had punched a wall the night after the hotel incident.

He left the court on Tuesday accompanied by his parents and his face shielded from cameras with a blue and white towel.

Mr Wells is due to return to Newtown Local Court on February 9.