I still have no idea about how scripting could improve the situation and how exactly this would need to be done.
Whatever, I found this:
And this involves manually renaming files and folders on local and remote devices.
I cannot do this.
All remote devices are not mine and I have no access beside what Syncthing offers locally. So I can only pause the folder at the local side or the remote device itself.
Does this help in renaming? How to handle this best?