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Walkden became the first Briton to successfully defend a taekwondo world title with victory in the +73kg category at the 2017 tournament.
She says she speaks "all the time" about MMA with double Olympic taekwondo champion and compatriot Jade Jones.
"You never know what the future holds," the 25-year-old said. "You'd have to train completely different."
Speaking to Radio 5 live's Sportsweek, she added: "If we got offered a spectacular fight, it was a one-off, a big event - then I would definitely do it."
Jones said last year that she could be tempted by a big-money move to MMA after the Tokyo 2020 Olympic Games.
Taekwondo world champion Bianca Walkden says she would take part in a "one-off" MMA - mixed martial arts - fight.