The influence of anti-gender movements is on the rise globally as they seek to prevent the expansion of transgender rights. In Germany, the anti-gender debate has gained renewed intensity in the wake of the publication of the draft Self-Determination Act in June 2022. Within this discourse, two prominent groups of actors emerged: gender-critical feminists and right-wing populists. Despite their divergent ideological and political positions, the affordances of social media provide them with a platform for collaborative interactions. Thus, under issue-related hashtags, the boundaries between these actors are becoming increasingly blurred. This research utilizes affect theory and analysis of hashtag activism to investigate the collective protest on Twitter against the proposed Self-Determination Act. Employing social network analysis (SNA), the study identifies pivotal structures and actors within the #FrauenSagenNein (#WomenSayNo) network. Additionally, qualitative content analysis delves into the narratives and sentiments employed in constructing hostile portrayals of transgender individuals. The findings illustrate that #FrauenSagenNein served as a bridging tool that connects gender-critical feminists and right-wing populist actors, leading to their intersection. Based on these findings, it is vital to critically monitor such alliances to counter the spread of binary gender norms and heteronormative beliefs.