Yes, you can purchase Minecraft and then download it on different devices without having to pay again, as long as you log in with the same Microsoft account that you used to make the purchase. This is in line with the Windows 10 sharing policy, which allows games to be installed on multiple devices under the same Microsoft account. Once you purchase the game, you can install it on up to ten devices, and as long as you are signed in with the purchasing account, you will be able to access and download the game without repurchasing it.
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