@Jasdela
Definitely seems like an oversight on our end. Thank you for letting us know.
I’ll probably be able to get this in the next release that we put out.
Here’s how to move SmoothSync into your project and start editing code if you can’t wait until then though:
Copy over the SmoothSync.h/cpp and State.h/cpp files from your D:\Programs\UE_4.26\Engine\Plugins\Marketplace\SmoothSync\Source\SmoothSyncPlugin or similar folder.
You may want to make these files first inside of your project then just copy over the content.
Then change the SMOOTHSYNCPLUGIN_API near the top of the header files (.h) to whatever your project name is (just the SMOOTHSYNCPLUGIN part is your project name, then put the _API at the end of it).
Make sure to keep the ALL CAPS for your project name even if it’s not in all caps when you made the project name.