Here are a few options for a formal title, depending on your focus:
Option 1 (Most direct and professional):
“Good Law Project Initiates Legal Action Against Ofcom Regarding Alleged Transphobic Misinformation on TalkTV”
Option 2 (Focusing on the regulatory failure):
“Good Law Project Challenges Ofcom Over Failure to Address Hate Speech and Misinformation on TalkTV”
Option 3 (Concise and formal):
“Good Law Project Files Lawsuit Against Ofcom Concerning Regulatory Inaction on TalkTV Content”
Recommendation: Option 1 is the most comprehensive for a formal report or article heading.