Since both are completely different implementations the syncing behavior might 
differ. I haven't paid much attention to the syncing behavior of the new kernel 
module but it might simply be more lazy than the FUSE implementation. Does it 
help to invoke `sync` manually? If yes, this may also be a workaround in case 
you really want it to write the data without delay.

I did try, yes. No fortune with manual sync and udisks or mount.

Here is a shell session, I think a pastebin is not needed given that it is short:

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(23:16) giovanni @ ~ $ udisksctl mount -b /dev/nvme0n1p5 -t ntfs3
Mounted /dev/nvme0n1p5 at /run/media/giovanni/Data
(23:16) giovanni @ ~ $ touch /run/media/giovanni/Data/ntfs_error.txt
(23:17) giovanni @ ~ $ ls -al /run/media/giovanni/Data/ntfs_error.txt
-rw-r--r-- 1 giovanni users 0 Nov 16 23:17 /run/media/giovanni/Data/ntfs_error.txt
(23:17) giovanni @ ~ $ echo "Using ntfs3" > /run/media/giovanni/Data/ntfs_error.txt
(23:17) giovanni @ ~ $ cat /run/media/giovanni/Data/ntfs_error.txt
(23:17) giovanni @ ~ $ udisksctl unmount -b /dev/nvme0n1p5
Unmounted /dev/nvme0n1p5.
(23:17) giovanni @ ~ $ udisksctl mount -b /dev/nvme0n1p5 -t ntfs3
Mounted /dev/nvme0n1p5 at /run/media/giovanni/Data
(23:17) giovanni @ ~ $ cat /run/media/giovanni/Data/ntfs_error.txt
Using ntfs3
(23:17) giovanni @ ~ $ udisksctl unmount -b /dev/nvme0n1p5
Unmounted /dev/nvme0n1p5.
(23:18) giovanni @ ~ $ sudo mount -t ntfs3 -o uid=$UID,gid=$GROUPS /dev/nvme0n1p5 /mnt/
(23:18) giovanni @ ~ $ cat /mnt/ntfs_error.txt  
Using ntfs3
(23:18) giovanni @ ~ $ echo "Using ntfs3 and mount" > /mnt/ntfs_error.txt  
(23:19) giovanni @ ~ $ cat /mnt/ntfs_error.txt  
(23:19) giovanni @ ~ $ sync
(23:19) giovanni @ ~ $ cat /mnt/ntfs_error.txt  
(23:19) giovanni @ ~ $ sync
(23:19) giovanni @ ~ $ cat /mnt/ntfs_error.txt  
(23:19) giovanni @ ~ $ sudo umount /mnt  
(23:19) giovanni @ ~ $ sudo mount -t ntfs3 -o uid=$UID,gid=$GROUPS /dev/nvme0n1p5 /mnt/
(23:19) giovanni @ ~ $ cat /mnt/ntfs_error.txt  
Using ntfs3 and mount
(23:19) giovanni @ ~ $

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You can see that when I try to overwrite the file content it just "appears" empty.

Unmounting and remounting the partition makes the content appear.

Bests,

-- 
Giovanni Santini