But they quickly became targets of the very violent misogynistic abuse they were fighting against.
Collective Shout managed to get payment companies to enforce their terms of service relating to the sale of the games, leading to the removal of thousands from platforms Steam and Itch.io in 2025.
"That unleashed a hellish fury against us," movement director Melinda Tankard Reist told AAP.
All five women have since been targeted with sophisticated and harmful tech-facilitated abuse.
It included death and rape threats, exposing of private details, hacking, threats to their financial systems and donors, and morphing their images into violent pornographic videos.
Fake newspaper headlines were generated, claiming the women had interfered with minors, while so-called "nudification" apps were used to place them in pornographic settings.
"There was nothing they didn't throw at us to try and destroy us and to try to stop us from engaging in the digital public square," Ms Tankard Reist said.
"Obviously it didn't work because we had our biggest year of victories last year ... but it does have a chilling effect."
The apparent aim was to silence Collective Shout and end their advocacy to stop sexual violence in games, but their experience reflects a broader threat to participation in online spaces.
The Online Hate Prevention Institute produced a report on the group's experience that will be launched at Parliament House in Canberra on Wednesday.
It highlights the lack of meaningful regulation against online abuse, which is only escalating due to the rise of artificial intelligence.
Misogyny was the central, organising force behind the attacks, it found.
"There's no meaningful protections for women online," said Collective Shout campaigns manager Caitlin Roper, who had her images used in fake pornography and depicted in extreme violence.
"Basically, men are permitted to threaten and terrorise women with no consequences."
Ms Roper went to West Australian police and was told they could not do anything if she did not know the identity of the perpetrators.
Australian Federal Police are investigating the attack on Collective Shout, but she said there had been no progress in more than a year.
Australia's eSafety commissioner has the power to investigate online abuse and demand tech companies take down harmful material with formal warning or fines.
But Collective Shout received thousands of threats and each complaint needed multiple pieces of evidence, including reports to the platform and links to the post and related profile.
"If you're affected by a mass volumetric attack, and these threats and abusers coming so fast, you literally can't keep up," Ms Roper said.
"But even when we did make reports, the response from eSafety was mainly that they didn't meet the threshold to be actioned.
"So men can threaten to rape and kill you and put your face on porn and post it online, and it's not bad enough to be actioned."
An eSafety spokesperson said the commission did not comment on specific complaints but it was not empowered to act when abuse was levelled at groups of people.
An AFP spokesperson said the agency was investigating the matter, along with state and territory police, but it would not be appropriate to comment further.
Among the report's 47 recommendations was for misogyny to be defined as gender-based hate speech and removed from platforms.
It calls for misinformation used to incite large-scale cyber abuse to be treated as a distinct harm, similar to racial vilification, and for social media platforms to actively demote content spreading abuse while promoting content debunking it.
In April, the federal government responded to a review of the Online Safety Act, which made 67 recommendations.
They included defining online hate material and volumetric attacks, measures that were not supported by the government.
Another recommendation to require major platforms to have a presence in Australia to better facilitate enforcement was not supported, as was a call to introduce a licensing scheme.
A spokesperson for Communications Minister Annika Wells said the nation's online safety laws were world-leading and would be further strengthened with a planned digital duty of care, which placed the onus on platforms to provide a secure environment for users.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
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