Swing and Unswing in one piece of music
At someone's suggestion: I began the piece with swing then I selected the first measure (in musescore 2), for NO SWING , went to palette and clicked on swing so the word 'SWING'" would appear then right clicked on it - to 'TEXT PROPERTIES' then swing settings and click 'OFF.' Worked well. This works the same for musescore 3.
in 3.x there's also a text "Straight", for exactly that purpose, under the 'More' button (or in the master palette)