Is it permissible to use forbidden methods – such as creating a fake account in the name of a girl and publishing sexually explicit phrases to attract sexually liberated women – with the aim of shutting down pornographic pages on the internet, knowing that this exposes me to reading content that incites lust and promotes immorality, and causes me to feel guilty?

May Allah reward your zeal for the boundaries of Allah. However, a Muslim must achieve that through legitimate means, without exposing himself to temptation. For averting harms takes precedence over realizing benefits. It has been previously explained that means share the rulings of their ends, and the criteria for whether the end justifies the means have been clarified. It is impossible to restrict or shut down such pages on social media. Perhaps the most suitable approach is to completely ignore them, or to merely post da'wah-related pictures and lectures on them.