Converting from swing to triplets

HI, Some times I write a song say in 4/4 time and simply select the MuseScore Swing option for the swing effect if required. Quite often I notice songs that should be in 12/8 time are written in 4/4 time but triplets are used. If I download a midi into MuseScore, and it is in 4/4 time but the notes are presented in four triplets so as to get the swing effect, is there any way to change this to normal notation (not triplets) and of course in 12/8 time and then select the MuseScore Swing option if required. Alternately, going the other way round, is there any way to change a song written in 12/8 time to 4/4 time with triplets?

Thanks,

Henry