Marc Skinner's side trained at Carrington in the morning before catching a flight from Manchester Airport.
The group will spend the week at the adidas campus in Herzogenaurach, and face Bayern there on Wednesday.
The match will be the Reds' third pre-season game so far after a draw with Leicester City and win over Everton.
WELCOMING BACK THE LIONESSES The trio were welcomed with a guard of honour formed by team-mates, staff and Academy players and were presented with flowers.
United's three World Cup Lionesses - Mary Earps, Ella Toone and Katie Zelem - reported back at Carrington for the first time since being away on England duty.