A Big Hero 6 sequel has yet to happen 10 years after the first film's release, and the only condition preventing it is a bad sign for it ever happening. Disney released the animated movie based on an obscure Marvel Comics team in 2014 and quickly found success. Big Hero 6 received very positive reviews, and Disney watched as its box office ballooned to over $650 million worldwide. That type of performance typically would mean that a Big Hero 6 sequel would be made, especially considering there was a post-credits scene teasing future adventures for Hiro and Baymax.
https://screenrant.com/big-hero-6-sequel-condition-not-happen/