Hello,
Welcome to Microsoft Q&A!
First of all, you can't upload such encrypted package to the Store. Store won't accept encrypted package because Store needs to recompile your package before publishing it. Another thing is that as far as I know Store will do the encrypt job for your app. When user downloads your app from the Store, the package is encrypted.
Thank you.
If the answer is the right solution, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.