Insync 3.2.1 on Fedora 32, 64-bit, using Google Drive.
This issue has been around for several versions now but I haven’t got round to reporting it before. It may even date back to the upgrade to version 3, I’m not sure:
What happens is that I put files into my local synced folder (always using the command line), and nothing will happen, i.e. uploading doesn’t start. This can go on certainly for hours with no activity unless I force it: I click on Pause Syncing, wait a few seconds, then click on Resume Syncing, whereupon Insync checks my entire local tree (very time-consuming as there are many small files) and then uploads the new files. Similarly, removing a local file will not remove the uploaded copy until forced in this way.
On the other hand, if I delete a file in the cloud, the local copy will be removed a few seconds later.
The “Sync new children of partially-synced folders automatically” option is enabled.