I spent years teaching irregular verbs to French teenagers, the school course books give lists of verbs to be learnt/learned by rote (horrible system). In the irregular verb lists they sometimes (not always) give the AmE version for information, while stressing that the BrE versions are to be used in all school work. So, the verb "to fit" is shown as regular in BrE and irregular in AmE. There are of course more verbs that are irregular in BrE and regular in AmE.