Steal some room from the Master closet and have the door open to the hallway. You could do a stacked W/D and have a folding counter/shelves next to the stack. Shouldn't be too difficult for a plumber to add a plumbing vent, given the adjacent hall bath.

Stacked units in the primary bed closet next to the tub wall. Huge closet, you will still have plenty of space in there.