Thank you, it's working for me.
I tested it with 2 apps and I was able to install both of them on my non-jailbroken device. It even saved the changes I did to the app on my jailbroken device (unlocked the full version via editing a plist).
I don't know if the ipas can be installed with Apple IDs other than mine (the one I downloaded the app from the AppStore with), but I assume so, since I installed it via a third party signing store, and they don't use my personal Apple ID.
For anyone curious about my setup:
iPhone 6s on iOS 13.5 jailbroken with Unc0ver
MacBook Air with MacOS Catalina
iPhone XS not jailbroken with a third party signing store that allows me to install custom apps
To transfer the ipas to my laptop or my other phone (the signing store doesn't need a PC) I used the iCloud Drive. Just download the files app and in Filza click "open in" and then "files app".
Sideloading should work too.