The error thrown by Google is because of how you have setup the shipping policy within your Google merchant center. You might have had an app previously which configured shipping settings for you which may lead to this issue. In this article we will see how the error can be fixed if this is the error bothering you.
Start by going to Shipping and returns:
Then if you see something like this(Weight_based_from_0.0...) :
You need to delete this and create your shipping profile again.
Once Deleted, You may receive another error if you leave it as it because you are not having any shipping profile at the moment so, don't forget to create another Shipping profile for the regions where you are going to ship.
Make sure you add the Shipping details properly for the regions you are serving and then Re-process the feed!
Voila🎉 The products should no longer be disapproved now :)
Do reach us out if you still continue to face the issue
David