Welcome!
Japanese maples are really pretty hardy. But they do take a long time to get to a good height.
My suggestion would be to harden them off when you get to your new location. That is, set them outside, but in a protected location and still in their pots for a few weeks. That will acclimate them. during the waiting period, I would prepare the holes for each sapling, making them very generous in size (at least a foot in diameter and a foot deep, even if the saplings are tiny), and filling them back in with a mix of the native dirt and some good compost. This will make a nice, loose soil for their little roots to spread out quickly in. Once hardened off,
plant them in their holes and water them in well. Keep them watered during their first few years. That is, water them weekly. If there is a dry spell you may even want to water them more often. If it rains and the soil stays moist, then nature has done the watering for you.
I have two Japanese maples that came as saplings from my mom's Japanese garden. The oldest one, (to the best of my recollection, it's been here maybe eight years ) is about eight feet high. It is still fairly small for a
tree, but I know it will be here for a long, long time.
