The read_all_orders permission seems to be a tricky one.
https://shopify.dev/tutorials/authenticate-a-public-app-with-oauth/#orders-permissions
I am currently building an app as well in which the read_all_orders permission was needed as per the initial plan but later I changed my mind not to use it after reading the complications. So my app is now planned to serve only for the orders that come in after the app is installed in the shopify store and does not support older orders for now.
Note : I am yet to initiate an approval request, hope this helps.