The 44-year-old, who came out as gay in 2009, was the victim of a homophobic attack in Cardiff on Saturday night.
Thomas chose to pursue restorative justice rather than press charges against a 16-year-old-boy, saying he “thought they could learn more that way than any other way”.
Serge Simon, vice-president of the French rugby federation, has since revealed his country’s national side will make a gesture of support to Thomas during their game against Fiji on Saturday night.
He told Thomas on Twitter: “All of French Rugby is with you regarding the homophobic molestation you’ve been victim of.
“To show our support, the French rugby players will wear a rainbow shoe lace during the France – Fiji game on Saturday night.
“We’re all in with you in this matter.”
Since 2013, charity Stonewall has been running the Rainbow Laces campaign to help ensure all lesbian, gay, bisexual and trans people can enjoy and be a part of sport.
Top rugby and football clubs across the UK have taken part in the initiative.
Thomas, who is the second highest try scorer in Welsh international rugby union history, made 100 appearances for his country between 1995 and 2007.
He also spent three seasons playing for French club side Toulouse during his career.
Following Saturday night’s attack, Thomas posted a video on Twitter.
He said: “This morning I have decided to make what I hope will be a positive video. Last night I was the victim in my home city of a hate crime for my sexuality.
“Why I want it to be positive, is because I want to say thank you to the police who were involved and were very helpful and allowed me to do restorative justice with the people who did this, because I thought they could learn more that way than any other way.
“Also to the people of Cardiff who supported me and helped me, because there are a lot of people out there who want to hurt us, but unfortunately for them there are a lot more who want to help us heal, so this I hope will be a positive message.”
Sky Sports is a member of TeamPride – a consortium of 10 companies committed to making sports everyone’s game – and also supports the Rainbow Laces campaign.