If you're using Preorder Pro + Back in Stock, yes, you can.
Go to theNotify Me settings page and scroll to the bottom right-hand corner. There, you can activate the option to apply “Notify Me” to all out-of-stock products.
Keep in mind, the app prioritizes thePre-Order function. This is a one-time setup step and won’t override existing preorder settings.
Originally from our Help Center