Place the veggie crumbles in a skillet over medium heat. Add the chopped green onions. Stir and cook together.
In the meantime, place the hoagie buns in a toaster oven, for about 3 minutes, until toasted.
Use a spatula to mold the veggie crumbles into 4 rows, about the size of your hoagie buns. Place 1 to 2 slices of cheese over each row of veggie crumbles. Once the cheese starts to melt, you're ready.
Add some vegan mayo to the top and bottom of each bun along with some ketchup. Then use your spatula to place one row of the vegan meat/cheese mixture on each bun. Serve warm.