The more-formal, older name for it is "mondegreen":

https://en.wikipedia.org/wiki/Mondegreen

This WP article and parent’s video are both fun, I enjoyed this momentary rabbit hole. The video above claims there’s a difference between a Mondegreens and Eggcorns, which is that Eggcorns are mis-heard phrases that have the same meaning as the original, while Mondegreens change the meaning. Plus the video has a clip of the ‘Mondegreen’ song sung with a strong Scottish accent - check it out if you didn’t make it that far!