I don't get it! How does SmartThings communicate with Ewelink?

Hi,
I’m new to this and mabye too old or too stupid or both to really master this smart home concept.
I have replaced most of my wall switches and are using Sonoff T0eu series stuff.
ST <=> IFTTT <=> Ewelink works like a charm for my needs.
But I can’t see that Ewelink can communicate backwards to ST via IFTTT and change the status of a switch in ST if I manually operate the actual switch. Is that normal?
A workaround is of course to create a trigger Ewelink <=> IFTTT <=>ST for every switch and status.
Is there any better way to make ST to sync with the actual status of the switches??
Rgds
Nils the Swede