The two had become the target of a wave of online memes, body-shaming and harassment.
Both Gadot, who played the character in the recent blockbuster movie, and its director Patty Jenkins tweeted support and encouragement.
The case triggered a fresh debate about online bullying.
When Amaya Suriyapperuma and fellow cosplayer Seshani Cooray decided to dress up as Wonder Woman at the Comic Con 2017 event in Colombo, they were not expecting it to send them on a rollercoaster ride of demeaning online memes.