With gPodder, you can use an online service to synchronize your feed list on several devices: https://gpodder.net/
In the preferences you just have to fill in your login and password.
This service does not work with the version of Papps: we get an error message.
But gPodder is natively portable. I have just done the test with 2 virgin versions and it's the Papps portability that seems to be the problem...
Do you think it's fixable?