I have the same issue. It was possible some versions ago, and for some Android apps it is still possible to save files (e.g. weirdly Opera can save websites, pictures, pdf’s from the net, but Vivaldi cannot), but others (e.g. threema, komoot, APKpure) simply crash or freeze when attempting such operation.
As I now have a Xperia 10iii and want to migrate the data to it, I’d like to have backups of some android apps using the builtin functionalities. However, some just don’t even have the ability to save anything - not even in the documents or download folders of the integrated android-storage. I have a XA2 Ultra, also on 220.127.116.11.
Would update to 18.104.22.168 as a first option to see if this improves the situation. If this doesn’t change anything, can anyone help?